Plaintext
FIRST LOOK: RASPBERRY PI MODEL A+
FREE DVD January 2015
DUAL BOOTING LEGAL RASPBERRY PI
INCLUDES ISSUE 1
& UBUNTU 14.10 GRUB 2 PATENTS BISCUITS
Work with multiple How the US courts are Build a snack protection
operating systems finally seeing sense system with Python
How your Linux
box beats
Windows 10
hands-down
34+ PAGES OF TUTORIALS
SYSTEMD Understand the changes that are coming to Linux
Januar y 2015 £5.99 Printed in the UK
OGGCAMP Inside the UK’s biggest hackery-makery happening
GIVE IT AWAY How we’re going to share our profits with the community
GOOGLE CARDBOARD INTERVIEW
DIY 3D TIM BRAY
Turn your phone into He takes your
an Oculus Rift privacy seriously
WELCOME
The season of goodwill
The January issue
Linux Voice is different.
Linux Voice is special.
Here’s why… GRAHAM MORRISON
A free software advocate
At the end of each financial and writer since the late
1
year we’ll give 50% of our 1990s, Graham is a lapsed
profits to a selection of KDE contributor and author
organisations that support free of the Meeq MIDI step
software, decided by a vote among sequencer.
our readers (that’s you).
T SUBSCRIBE
his is our tenth issue, and as per our crowdfunding promise
No later than nine months when we launched the magazine, it marks the release of
2
after first publication, we will
relicense all of our content under
issue number one under the terms of a Creative Commons
licence (you’ll find it on this issue’s DVD already). The licence we
ON PAGE 62
the Creative Commons CC-BY-SA chose was CC BY-SA, which means you can do pretty much
licence, so that old content can anything you like with our content – even sell it, as long as you
still be useful, and can live on even credit the source. We all feel like we’re breaking new ground with
after the magazine has come off this approach, and we know of no other magazine that does the
the shelves. same, let alone a magazine funded by the community, available on
international newsstands, and run by a few people from their
We’re a small company, so kitchens and bedrooms.
3
we don’t have a board of As our first year draws to a close, we’re also starting to think
directors or a bunch of about how we’re going to give our profits away, and we’ve outlined
shareholders in the City of London a prototype for the process on p36. Now is the time to get involved
to keep happy. The only people if you want to have a say, and we’d love to have your input. Take a
that matter to us are the readers. look at our redesigned LinuxVoice.com for further details, and as
ever, feel free to contact any of us directly.
THE LINUX VOICE TEAM Graham Morrison
Editor Graham Morrison Editor, Linux Voice
graham@linuxvoice.com
Deputy editor Andrew Gregory
What’s hot in LV#010
andrew@linuxvoice.com
Technical editor Ben Everard
ben@linuxvoice.com
Editor at large Mike Saunders
mike@linuxvoice.com
Games editor Liam Dawe
liam@linuxvoice.com
Creative director Stacey Black
stacey@linuxvoice.com
Malign puppetmaster Nick Veitch
nick@linuxvoice.com
Editorial contributors:
Russell Barnes, Chris Brown, Mark
Crutch, Marco Fioretti, Josette Garcia, MAYANK SHARMA BEN EVERARD MIKE SAUNDERS
Juliet Kemp, Vincent Mealing, Simon My biscuits are always being The Raspberry Pi Foundation Ben combines robots, artificial
Phipps, Les Pounder, Tariq Rashid, stolen. Which is why Les gave us exclusive access to their intelligence and a competition in
Adam Saunders, Valentine Sinitsyn Pounder’s early warning system new A+ model, which they’ve an ace tutorial about building
is so completely awesome. p78 made even cheaper. p28 your own Skynet. p104
www.linuxvoice.com 3
CONTENTS
January LV010
Spreading the word of Linux since 2014. Wait – it still is 2014!
20 REGULARS
SUBSCRIBE News
06
ON PAGE 62 Italians won’t have to pay the
Windows tax any more, plus
Microsoft loves us.
08 Distrohopper
Netrunner, Knoppix, BackBox
and Picaros Diego all come
under the microscope.
10 Gaming
Borderlands: the Pre-Sequel
Linux vs Windows – coming to a Linux machine
near you.
Speak your brains
Why we’re so, so glad we’re not 12
Another Vim convert, a silly
using Windows any more. typo and a call for freedom – all
written by you lovely lot.
16 LV on tour
Brought to you by Python in
Dublin, OpenRISC in Munich
42 and Open Rights in London.
18 OggCamp
The biggest Geekfest in the
UK extends its warm embrace
to us all.
36 LV profit sharing
We promised we’d give away
half our profits – here’s how
Tim Bray
we’re going to do it.
56 Group test
The man behind the Six of the best lightweight
Linux distros whittled down
XML spec wants to to one champion.
talk to you about 62 Subscribe!
It’s not just an operating
online privacy… system, it’s a way of life.
Join us today!
64 Core technologies
Dr Brown unearths access
controls: groups, users and
permissions.
68 FOSSpicks
Freer than a radical with a
dangling covalent bond, (but
not as damaging to cells).
110 Masterclass
The tools to rip DVDs to video
28
PI MODEL A+ 40 FAQ: RISCOS 32
PATENTS files and the knowledge to use
Meet the latest No, this is not an Praise be for the US them to do just that.
product from OS for skydivers or Supreme Court being 114 My Linux desktop
the Raspberry Pi fans of the Japanese sensible in the face Enter Lennart ‘man behind
Systemd’ Poettering’s Bauhaus
Foundation – the all delicacy, fugu. It’s of a load of patent den of geek.
new Model A+. reduced and open. nonsense.
4 www.linuxvoice.com
TUTORIALS REVIEWS
76 78
48 Ubuntu 14.10
The biggest distro pauses to
i3: Learn a tiling Raspberry Pi: Use draw breath before next year’s
big Mir/Systemd release.
window manager different kinds of input
Make better use of your screen Use your Pi to protect a plate
space and kill the mouse for good. of biscuits from interlopers.
82 86
50 Fritzbox
If you’re looking for the end of
level boss of routers, we may
just have found it for you.
OpenBSD 5.6
Markdown: Write once, Linux 101: Get the best
52
Try an alternative Unix
publish anywhere out of Systemd derivative with a focus on
stability and security.
Publish your content in a simple Love it or hate it, Systemd is here
format that looks here to stay. – you might as well use it.
90 94
53 Google Cardboard
Google now wants to control
your senses, with its homespun
3D headset for smartphones.
Grub 2: Heal your Olde code: Atlas – the 54 Books … and a film
bootloader UK’s supercomputer masquerading as a book!
Citizen Four, about the
How to fix a broken installation The transistor revolution brought Edward Snowden leaks.
without losing all your data. supercomputing to Manchester.
100
Code fractals 102
Code ninja: Stdin 104
Robocode:
with Python and stdout AI warfare
Introducing the Chain commands Program primitive
Julia set. together for fun. robot brains.
www.linuxvoice.com 5
ANALYSIS
NEWSANALYSIS
The Linux Voice view on what’s going on in the world of Free Software.
Opinion
The code audit mirage
What does it take to keep open source code secure?
Simon Phipps undocumented functions.
is president of the Audit is a reasonable way to
Open Source Initiative
give customers of this
and a board member
of the Open Rights proprietary code confidence
Group and of Open that it behaves in the way
Source for America. the vendor describes. But
open source code is not a
product until a vendor
packages it as one. Until
then it is a tool, waiting to be
I
n the wake of Heartbleed and other deployed by a suitably
serious bugs found in open source code, knowledgeable person.
I keep hearing calls for “audit”. For
example, the European Commission is What should we do?
considering whether to budget for security First, we should be demanding of
audits as part of its encouragement of open suppliers who deploy open source
source software adoption. That’s something code as part of a deliverable with
I never heard in all my years at technology security aspects that they audit the
corporations. We discussed testing code. If your supplier does not
strategies, deployed “pen testing”, did employ committers on the code they are
automated code scans, used assertions in trying to sell you, or at very least have a
code to back up several of those test paid business relationship with someone
strategies, and so on. But “audit”? I never who does, don’t buy.
remember hearing it mentioned. Second, as community developers we
An audit is exactly the wrong strategy for should be performing regular scans of the
open source. It spends money on finding code we share using a tool like Coverity Scan. One of the major reasons Heartbleed happened
fault without fixing anything. It reflects a It’s a free-of-charge proprietary offering that was a lack of new eyes coming into the
worldview that open source software is a analyses even the largest codebase and OpenSLL project
product someone else is responsible for, identifies common programming errors like
rather than a shared resource everyone is uninitialised pointers, buffer over-runs, diversity of communities. A project that has
responsible for. If you don’t trust the code, unreachable code and so on. It produces a very few different sources of external
you should be pointing your finger at detailed, actionable report that community motivation for its committers – all the same
whoever deployed it, not at the code. The programmers can then cherry-pick to fix the employer, for example – can easily neglect
only time to fall back to an audit is when the serious issues identified. Coverity Scan also the steps necessary to keep quality high.
collaborative developers refuse to co- produces a useful code quality metric, which Open source code is neither more nor less
operate, as happened with TrueCrypt. allows tracking of code improvement trends secure intrinsically -- all code has bugs, and
All code has bugs. Secret code can also as well as highlighting regressions. sometimes they lead to security exposures
have intentional back-doors and Third, we should keep an eye on the and subsequently to exploits. But open
source, properly maintained in a diverse
community, can have them fixed faster and
“An audit is exactly the wrong strategy – it spends can use tools that publicly expose issues.
money on finding fault without fixing anything.” Let’s make the code better and not allow
open source to be misrepresented.
6 www.linuxvoice.com
ANALYSIS
Debian • Italy • Tor • MS loves Linux • Adobe • Ubuntu is 10 • HTML 5
CATCHUP Summarised: the biggest news
stories from the last month
Debian fork proposed due Italian Supreme Court Tor Browser 4.0 released
1 to Systemd adoption 2 bans “Microsoft tax” 3 with Meek transports
Systemd (see page 86) is If you buy a PC with Windows Thanks to the new Meek
being adopted by most major distros pre-installed, but never even boot that pluggable transports, Tor can relay
now, but not everyone is happy with OS and install Linux instead, you won’t data via third-party servers such as
the change. A group of “veteran Unix have much luck getting a refund for content delivery networks and cloud
admins” have suggested that it’s time the unused software. But times are hosting services, making it harder for
to fork Debian, after the distribution changing: the Italian Supreme Court governments to block Tor connections.
decided to use Systemd. The website has ruled that this “Microsoft tax” is www.torproject.org
at www.debianfork.org outlines their illegal, and anyone should have the right
reasons – but it has already been to get their money back if they buy a PC
parodied on www.forkfedora.org. Given and use a different operating system.
the vast size and scope of the Debian The Free Software Foundation has a
project, a successful fork would be a more detailed explanation here:
mountain of work, but let’s see… http://tinyurl.com/klgp5gj
Microsoft CEO Satya Adobe discontinues ChromeOS drops ext
4 Nadella: “We love Linux” 5 Reader for Linux 6 support, puts it back in
No, this isn’t a delayed April We know that plenty of Linux This might not seem like a hot
Fool’s joke. Microsoft’s new-ish boss and FOSS users aren’t big fans of news story, but it shows how effective
has proclaimed that the company now Adobe, especially given the horrendous a vocal community can be. Developers
loves Linux, given that 20% of its Azure bloatware its PDF Reader has become. working on Google’s ChromeOS
cloud platform customers are running Now Adobe has pulled the plug on platform quietly dropped support for
the open source OS. This is in stark Reader for Linux – not a big deal for Linux’s native ext filesystems, so you
contrast to the remarks made by many people who are using arguably couldn’t use them on external media
Nadella’s predecessor, Steve Ballmer, superior programs like Evince, but such as SD cards or USB keys. This led
who famously described Linux as a frustrating for others. We asked our to much gnashing of teeth online, with
“cancer”. Nadella sees things differently Twitter followers what they thought, a huge number of complaints being
though: “I don’t want to fight old battles. and many of them still need Adobe’s made, so Google relented and put the
I want to fight new ones”. A real change tool for filling in certain forms which filesystem support back in. “We’ve
of heart, or just empty words? don’t work well in the FOSS equivalents. heard you loud and clear”, said one dev.
Ubuntu turns 10! W3C finalises HTML 5
7 Yes, the distro that 8 standard, finally
introduced many millions This isn’t directly related to
of people to Linux and FOSS has Linux, but it’s big news for OSes that
just hit double digits. Over a decade use web apps, such as Firefox OS. After
ago, Mark Shuttleworth pored over eight years of work, the World Wide
archives of the Debian mailing lists, Web Consortium (W3C) has finalised
gathered together some of the the HTML5 standard. Sure, many web
distro’s most notable developers, and browsers have been implementing
decided to get Linux onto mainstream HTML5 features for a while, such as
desktops. The first release was the improved media support, but now
Warty Warthog (aka 4.10), shown on that the standard is finished, browser
the right. Remember that chocolatey devs can be sure that the specs won’t
brown theme? Anyway, happy birthday change beneath their feet.
Ubuntu – here’s to another 10 years! http://tinyurl.com/ohlz4x6
www.linuxvoice.com 7
DISTROHOPPER
DISTROHOPPER
Our pick of the latest releases will whet your appetite for new Linux distributions.
Picaros Diego
Linux for children.
T
here are a few distributions aimed at
children: Doudou springs to mind,
and there’s also Sugar on a Stick.
Both of these are based on the idea that you
need to protect children from the
complexities of the computer (and protect
the computer from the children). Picaros
Diego is different. There’s nothing stripped-
down or shielded from view. Instead, it’s a
normal Linux distro with a brighter, more
kid-friendly interface.
The desktop wallpaper perhaps best We were too busy playing Secret Mario on Picaros Diego to write a witty or interesting caption.
exemplifies this. On one hand, it’s a colourful
cartoon image designed to interest young file manager. In the programming category, little young for a system like this, but the it
children. Some of the images on the we were slightly disappointed to discover it may well work for children on the upper end
landscape are icons for games, and this only had Gambas (a Visual Basic-like of that age range.
should encourage children to investigate the language), and not more popular teaching Overall, we like the philosophy of wrapping
system rather than just relying on menus. languages like Scratch or a Python IDE. Linux is a child-friendly package, but not
On the other hand, it still displays technical However, it’s based on Debian, so you do dumbing it down. Picaros Diego won’t work
details such as the CPU usage and the RAM have the full range of software available for every child, but if you have a budding
and Swap availability. through apt-get, so this isn’t a problem. geek in your midst, it could be the distro to
It has kids’ games and more technical The project website lists it as suitable for bridge the gap between highly simplified toy
software such as the Midnight Commander children aged three to 12. We think three is a distros and normal operating systems.
BackBox
Penetration testing never looked so lovely.
B
ackBox is a distro for people even though they’re command line-based,
interested in computer security (call and clicking on them brings up a terminal
them whatever you like: crackers, window with the help text of the tool. This
hackers, penetration testers or annoying might seem a little strange to people used to
sods who cause you to have to deal with regular Linux distributions, but it makes it For most of the time we’ve known about this
selinux). It’s based on Ubuntu with a much easier to get started with the tools. distro, we’ve been pronouncing it Blackbox. We
customised LXDE graphical environment, Especially if – like this author – you have a apologise to all concerned.
and a whole lot of tools to help you crack, terrible memory for commands you only use
sidestep or otherwise bypass security occasionally. PPAs for just about anything) and it’s
measures. There are also additional tools We’re relative newcomers to Backbox, but lightweight. If you’re completely new to this
for pentesters such as the MagicTree it’s quickly becoming our favourite field, you might be better off with Kali, as
reporting software. penetration testing environment. It looks there’s more support for this distro, but if
As is customary in pen testers’ distros, the nice, it’s easy to use, it’s got the full set of you’re fairly familiar with Linux, you shouldn’t
applications menu includes all of these tools Ubuntu software available (you can add have any trouble at all with Backbox.
8 www.linuxvoice.com
DISTROHOPPER
Netrunner Rolling Release
A surprise find on our torrent server.
W
e’re running a Torrent server at
Linux Voice, partly to help take
some of the bandwidth load off
individual distro projects, but also because it
provides us with a useful insight into what’s
popular at the moment. One of the surprise
successes has been Netrunner Rolling
Release. After Knoppix (see below) and Tails,
the distro for the privacy-conscious, it has
the highest share ratio of any of the distros
we’re hosting. Share ratios are an odd
statistic (they provide a rough indication of
the number of times something has been
uploaded), and aren’t an accurate
representation of popularity. Still, this is a
high position for a relatively unknown distro.
The main version of Netrunner is based
on Kubuntu, while the rolling version is
based on Manjaro (and by extension, Arch). Netrunner Rolling also comes with a few games such as BurgerSpace to help you unwind after a
This means that underneath, there’s quite a stressful upgrade by smashing hamburgers.
lot of difference between the two, even
through they both carry the Netrunner Firefox in Netrunner comes with Adblock There’s space for distros that package the
name. Both have a great KDE interface – not plus installed, and DownloadHelper (an vanilla versions of software, but we prefer it
just the usual defaults, but an interface extension to help you grab images and when distro maintainers put their personal
that’s been crafted to look nice out the box videos to watch later). It’s little tweaks like stamp on the software and help the user get
– but below this they have little in common. these that make using Netrunner pleasant. set up with a good system.
Knoppix The original live Linux distro is still going strong
There was a time – far back in the distant past – when you couldn’t
try Linux without installing a distro. Then along came Knoppix, with
the revolutionary concept of running Linux directly from a DVD
without installing anything, and the live distro was born.
These days, of course, almost every distro comes as a live CD (or
DVD) that you can try before installing directly from the live session.
So is there still a place for a live-only distro like Knoppix?
Absolutely! The simple reason is that while many distros can run
live, most aren’t designed to do so as a matter of course. Knoppix is.
This means that it comes with a walloping bundle of software that
should be sufficient for almost any situation. For example, it comes
with everything you should need to get online on almost any type of
connection. ISDN line? Fine. 3G dongle? No problem. Need to start
an SSH server? Included. In fact, it’s hard to find an area that
Knoppix doesn’t come with software for. It can help you recover a
broken machine, or operate as a main operating system in a machine
with no hard drive.
With a live distro, you’re also stuck with the look and feel that
comes pre-configured (unless you want to make changes every time
you reboot). This means it’s that even more important than normal
that it looks good. Knoppix has a slightly unusual combination of
LXDE (usually known for its minimalism) and some pretty heavy
graphical effects that we’re more used to seeing on KDE. However,
the end result is an nice looking desktop that should run reasonably
on most hardware.
Knoppix is one of those distros that you should always have a
copy of, because sometime, probably when you’ll least expect it, it’ll
get you out of a sticky situation. The Knoppix desktop might be a little unorthodox, but it works well.
www.linuxvoice.com 9
GAMING ON LINUX
GAMING ON LINUX
The tastiest brain candy to relax those tired neurons
DON’T PANIC!
Borderlands: The Pre-sequel
Shoot ’n’ loot on the moon.
N
ot finding enough loot in Borderlands 2?
Well we have you covered, as
Borderlands: The Pre-sequel has been
released on Steam for Linux.
Borderlands: The Pre-sequel is a mix of frantic
first person shooting with RPG mechanics that
works out rather nicely. As you shoot and loot
Liam Dawe is our Games Editor and
the founder of gamingonlinux.com, your way through the game you will be able to
the home of Tux gaming on the web. level up, and unlock special abilities.
The Borderlands series is known for injecting a
A
re you feeling nervous about fair bit of comedy into the game, so don’t go
Steam Machines and thinking this is some sort of Call of Duty-class
SteamOS? Are you worried
serious shooter. them a quick invitation on Steam, and like magic
about what will happen to Linux
gaming if they fail? We are here to What makes the Borderlands series so different they enter your game world.
settle those worries over a hot cuppa is a mixture of a few things, the most important The day has come for Linux gamers to truly
with some thoughts of our own. of which is the loot system. Each gamer could show our numbers. This is the first time we have
Let’s start with some facts about end up with a completely different arsenal of been able to give a major publisher sales
where Linux gaming is right now;
weapons compared with your friends online. Are statistics from Linux gamers to compare them
Valve’s juggernaut of a store is now
serving up over 700 Linux-compatible you jealous of their sniper rifle that does fire properly side-by-side with Windows & Mac, so it’s
games with no sign of slowing down. damage? No problem: just show off your assault time to show them our numbers!
Only recently have some big rifle grenade launcher (and yes that’s a thing!).
AAA-class releases hit Linux too, so The online modes are also what makes it a Publisher 2K Developer Gearbox/Aspyr Media
not only are we getting more, but we Release Date 17 October 2014 Store http://store.
great experience, as it’s all completely seamless.
are getting games with much bigger steampowered.com/app/261640
budgets too. Teaming up with people is as simple as sending
GOG deserves an honourable
mention now as just recently it hit
100 Linux games in its catalogue, and This is Linux’s first ever AAA
considering that it has only same-day Linux release.
supported Linux since July of 2014
that’s a pretty quick jump. GOG will
also support Linux with its recently
announced Steam-like client called
‘Galaxy’, and since it has no ties with
Valve and Steam it will continue
supporting Linux regardless of what
happens with the Steam Machines.
Why are we noting all of this? Well,
this success has all come without a
single Steam Machine being released,
so with all this happening for us
gamers we think that Linux gaming
will carry on being perfectly healthy
even if Steam Machines are a flop.
A Linux-based gaming machine
won’t exactly be an overnight success
anyway, but with Valve we should see
a slow and steady push to increase
Linux games to help them succeed
“Borderlands: The Pre-sequel is a mix of frantic
with their Linux-based initiative. first-person shooting with RPG mechanics.”
10 www.linuxvoice.com
GAMING ON LINUX
Super Win The Game ALSO RELEASED…
Here comes the nostalgia train!
R
emember the days of being Game which is also available on Steam for
frustrated trying to complete Linux, and it expands on it rather a lot with
platformers on your old games a lot more content.
consoles? Well Super Win The Game Unlike the free game that came before
should bring back a lot of memories, as it, Super Win The Game is not just a
it seeks to emulate the look and feel of a standard platformer, as it blends a mix of
lot of retro games, so you could call it a adventure gaming along with some slick
homage to retro games, and in our eyes platforming moves. Eufloria HD
it’s one of the best at achieving this effect. There is no combat in this game, so A revamp of a well-received ambient strategy
The game comes with full game-pad if you’re a pacifist looking for some non- game that is now on Linux. A great way to relax
support as standard, so it can really feel violent fun, this is for you. your tired mind with lovely ambient music, and
the part and a game like this feels better easy to learn strategy controls make it a
winner this issue.
with one too. Publisher Minor Key Games Developer Minor The style of the game is just beautiful with
Super Win The Game is the sequel to the Key Games Release Date 1 October 2014 Store
http://store.steampowered.com/app/310700/ the minimalistic, but gorgeous graphics.
free hit indie game You Have To Win The Now, go spread your seeds across the universe!
http://store.steampowered.com/app/221180
The game uses a CRT effect to
simulate old monitors
Windward
Landlubbers need not apply. Windward is a
procedurally generated (it’s all random) naval
0 A.D. combat and exploration game designed to be
played either by yourself, or team up in co-op
with friends.
Setting the future standard for open source games. You can fight against pirate ships, do a little
0
trading or just explore the high seas.
A.D. has unleashed its 17th alpha It’s currently in ‘Early Access’, so it’s not yet
version of the open source real complete, but early reviews are positive.
time strategy title that aims to be http://store.steampowered.com/app/326410
historically accurate.
0 A.D. is aimed at fans of games like
Microsoft’s Age of Empires series of
games, and plays a lot like them. The
major difference is that you don’t upgrade
through different ages like in the AoE
series of games.
The new release is a whopper with New features are but a tip of the iceberg
a major rebalance to the combat, but for this latest alpha as 0 A.D. has seen
formations have been removed for the a wave of performance enhancements
moment to be reworked. It also includes too, so you should notice a better overall Screencheat
a much smarter AI that can now deploy framerate, and this is probably one of the Do you like to play co-op with your friends and
naval transport ships to hop to different most important fixes as the late-game got peek at their screens? We do too! Lucky for us
islands, so the AI will no longer stall on rather sluggish in previous alphas. Screencheat has been released in full on
Steam, and the main hook for it is you actually
naval-based maps. Combat units can now need to use other people’s screens to find
garrison walls directly for extra defence, Developer Wildfire Games (and contributors) them, as everyone is invisible. Madness!
and when you do this you can even see Release Date No ETA for the final release Store http://store.steampowered.com/app/301970
http://play0ad.com
them on top of the walls.
www.linuxvoice.com 11
MAIL
YOUR LETTERS
Got something to say? An idea for a new magazine feature?
Or a great discovery? Email us: letters@linuxvoice.com
LINUX VOICE STAR LETTER
FREE YOUR CARPALS
This is my first letter/email I think I have got the areas
ever to a magazine but I I need to target but knowing
felt compelled to write it as which shortcuts to learn
Linux Voice is such a good straight away and which to
read (subscription to it from ignore or put lower down on
my girlfriend – an amazing the priority list is very much
present). prone to trial and error (my
This year, spurred on by desktop environment is
your magazine, I have been KDE which can be baffling
compelled to try as much as at times) Learning a whole
possible to banish the mouse. slew of new shortcuts can be
I am doing my damnedest to terminally off putting. Is there
remove the rodent from my a site/book/font of knowledge
desktop to increase long term that can help with prioritising
productivity. However, I am which shortcuts to learn
finding it very tricky. first to dramatically increase
It’s tricky as there does productivity. I do recommend There’s a learning curve with all-singing, all-dancing text editors like
not appear to be a clear people reduce mouse usage. Vim, but once you’re used to living with it, you’ll never look back.
and obvious path to doing Its amazing what the meta key
this. Increased use of the and a cursor key can achieve composed in Vim – I’m a new to go cold turkey on the mouse
command line (using Yakuake together. convert. (RSI gets a bit much when
and Terminator), changing/ Laurie James, London you’re constantly clicking and
learning desktop environment PS Thank you for the great Mike says: Hurray! Another typing), Terminator is brilliant for
shortcuts and software Vim tip of always pressing the convert for the Vim cause. anyone wishing to improve their
shortcuts are the areas I am Esc key after inserting text. Welcome to our ranks, Laurie. productivity – if you haven’t tried
concentrating on. PPS This email was While we do occasionally try it yet, give it a go!
MORE TO LATEX
Of course it’s important to Clamtk is a useful graphical front
understand the principles of end, but some distros only provide
markup of TeX and LaTeX, as Dr ClamAV, which needs use at the
Sinitsyn elucidates [in LV009], but command line.
the easiest way is surely to use Dave Postles
LyX, which should be available in From my Trisquel Linux desktop
all distro repositories. As for virus
checking, it is useful to do so to Andrew says: Cheers Dave – although
avoid passing on any infected there are no viruses out there for
document which some Windows Linux, it’s good if you’re running a mail
user might have sent to you and server to help keep the internet clean If you want most of power of Latex but with a shallower learning
which you distribute further. for poor old Windows users. curve, give its graphical cousin Lyx a go.
12 www.linuxvoice.com
MAIL
IT’S ONLY WORDS AN ODD TYPO
In your December edition you I looked at your Issue 8 DVD
replied to Richard Bosworth about and the envelope for it and was
explaining free software to ‘the surprised to see a typo in what
masses’. seemed an unlikely place – the
In a somewhat similar situation legal disclaimer. “Legal: Linux
I finally worked out that the Voice cannot accept s for any
message was not so much not disruption, damage and/or
getting through as being totally loss to your data or computer
inverted in translation. The person that may occur while using
I was talking to turned out to treat this DVD.” Granted, this is the
‘free’ as a synonym for ‘worthless’ typical legalistic covering of your
and ‘volunteer’ as meaning posterior. Your readers most likely
‘someone who isn’t serious’. Given understand that and would never
The ethical stance taken
that to him ‘proprietary’ meant same problem. The Free = Worthless consider giving you any S. I can
by Richard Stallman
‘valuable’ and only a company interpretation is fixed in many people’s and the Free Software only guess what other letters of
could possibly be relied upon for heads by years of experience, so it’ll Foundation is exactly the alphabet you wouldn’t want to
support and that was it: I was be hard to overcome. Next issue we’ll right – it’s just getting accept.
snookered. go back to basics with a look at why it across to the masses Roy Birk
Tom Groves, Ashford, Kent free software matters – not just an that’s proving difficult.
exploration of the features (though Andrew says: Hmmm. It’s true, we do
Mike says: We’ve had a few replies do feel free to turn to page 20 for our not accept any S. We prefer pounds,
on this subject, and it’s troubling thoughts on Windows vs Linux), but euros or dollars. Or bottles of whisky.
that so many people are finding the as an ethical choice. I’m as baffled by that as anyone.
PRAISE. KIND OF
I love your magazine and podcast, If you move on to page 46, there
keep up the great work! is a review of CentOS 7. Obviously,
However in reading issue #6, I it was available in time for a review
found something that my pedantic to make it to print. Thanks again
nature could not reconcile. On for the hard work and dedication to
page 9 when discussing Red Hat the open source community.
Enterprise Linux 7, the article Todd Campbell
ends with “The CentOS team are
working on the community build, Graham says: Rations have been
which may even be available by reduced and the team will be flogged Rest assured that we won’t be
the time you read this.” until performance improves. accepting any S relating to this issue’s
DVD either.
www.linuxvoice.com 13
MAIL
MORE TINKERING!
I would first like to congratulate
your entire team for a job well
done. I got interested in Linux
Voice the moment I saw your
second issue, and have since
become a subscriber. Just the
core technology section makes
the magazine a must read. I am
a hardcore Windows user and
though I use Linux at work I wasnt
particularly attracted to it until I
started reading your magazine. LV
has encouraged me to try out new
distros in the past few months and
after trying CrunchBang, Bodhi,
Manjaro, CentOS and Arch I have
finally settled down with Gentoo.
Formatted my Windows box and
put in Gentoo! And loving every
moment of it. Thanks a ton LV!
I would like to request that
There’s more tinkery fun
you include an article type for hardware diagnostics utilities etc. Linux and are loving it, despite the
in the pipeline – like the
tinkerers like myself in every Saptarshi culture shock. We’d really like to delve driver we wrote for this
issue which could be about say deeper into some subjects/projects, USB toy car.
writing your own Linux device Graham says: Wow! Welcome! I as you suggest, and we’ve got some
driver (something a little more know a few hardcore Windows users great plans for longer form projects
in-depth than issue 2 or perhaps a and none would give up their OSs that spend more time relishing in the
series) or tinkering with Awesome without a fight, so it’s wonderful to details. If anyone has a great idea for
WM’s configuration or just some see you’ve found your way over to an in-depth project, let us know.
YOUR AD
HERE
14
Email andrew@linuxvoice.com to advertise here
MAIL
WHAT DISTRO?
I started using Linux with need serious attention, but a basic
Slackware 96, or was it 3.0, and distribution, without updates,
went through Red Hat and Gentoo would give me, at least, some
but failed with Arch Linux. Now I’m relief.
running Linux Mint 17 – with KDE, Ron Petch, East Gosford NSW
of course.
My requirements are simple, the Andrew says: Clem Lefebvre, the chief
internet, some games, email and boss of Mint, says “As a general rule...
multimedia. I do have a PostgreSQL unless you need to, or unless you
database using Tcl and Tk. really want to, there’s no reason for
With progressive upgrading you to upgrade”, which is probably a
and updating I have not gained good sign that you shouldn’t. We’ve
in functionality, but have lost started to fall out of love with Arch
things. I can’t get Compiz to do recently due to some breakages, so I
the impressive rotating cubes wouldn’t recommend that. How about
anymore, giver has been and gone, Debian? You get the security updates,
and now World Of Goo ( I was but there’s no risk that the developers
up to chapter 2 ). I get segment will rush forward a feature causing
faults, which I presume means your software to break.
incompatible libraries.
Where can I find a distribution,
which is stable and “old
fashoned”, to get these back? I Slow and steady wins the race, if the
can understand security and UEFI race is all about not breaking things.
WE HAPPY FEW
I first became aware of and sandwiched between them. struck me as more than a little odd
interested in Linux some years (Come back Jonathan Roberts, to expect a magazine devoted to
ago through Micro Mart magazine, all is forgiven!) And there among Linux to be expected to promote
which I read for three or four years. the contributors another familiar something which, I quote, “has
However, gradually there was less name, Mayank Sharma. What I nothing to do with Linux.” I was
to interest me in it than hitherto. have read so far I have understood. not all that surprised that you have
Then I spotted a Linux magazine, I like the style and appearance of ignored it.
which must remain unidentified, things so I fancy you have just A Geoffrey Mort
and I started to take it on a regular gained a regular reader.
basis (despite the wife’s tut-tutting I have an issue you may well Andrew says: If you’re looking for a
about the cost!). However more be able to help me with. I have for version of Linux to choose, you could
recently I have found that more the last two years been intending do a lot worse than try Lubuntu from
of the content has been ‘over my to install a Linux distro on my this issue’s DVD. It’s low on system
head’ (I’m not in the first flush of machine. At the moment I use requirements and we’ve included
youth) and I had begun to wonder Windows (excuse the language!) it in its 32-bit version, which, if
whether I ought to overcome my XP and have absolutely no your machine is still running XP,
innate product loyalty thing and intention at all of upgrading. I’m guessing will probably fit your
discontinue. However, not being overly hardware better than the KDE version.
Last week in WH Smith’s I knowledgeably about computers And if you’re looking for help with
noticed Linux Voice 008, but and computing, I have yet to take Linux, the north west of England
didn’t pick it up. Until, that is, in the plunge. I wondered if there is a fantastic place to be. Preston
the supermarket on Friday, when I might be an experienced Linux and Blackpool have active hacker
saw it again and decided to have a user in the Bolton area, which is communities, and the Manchester
look. And there, to my amazement where I live, upon whose guidance Raspberry Jam (the Raspberry Pi is
was a familiar face, Graham and help I could call. If there is just a Linux box, remember) is one of
Morrison, no less, and then someone they can email me at the biggest around – not sure about
three more familiar faces hirsute AGeoffMort @tiscali.co.uk. Bolton itself, but I’m sure there are
editions of Andrew Gregory, and Finally, I noticed the letter in people near you to offer a helping
Mike Saunders, with Ben Everard Linux Voice by David Walker. It hand. And I’m glad you’ve found us!
www.linuxvoice.com 15
LUGS ON TOUR
LUGS ON TOUR
ORCONF 2014
Mike Saunders finally becomes an alpha geek by hanging out with CPU designers.
I
f you’ve not heard of OpenRISC
before, turn to p40 for our
introduction to this open source
processor design. OpenRISC has
been around for well over a decade,
but in recent years it has seen a
surge in popularity – partly thanks
to the overall increased interest
in open source, but also due to
the boom in mobile devices. So
for the last three years, OpenRISC
developers, users and curious
onlookers have gotten together for
their annual conference, and this
year it took place on the 11–12
October in Munich.
Why Munich? Well, OpenRISC
is used extensively in the city’s
Technical University for research
into processor designs. Stefan
Wallantowitz, a research assistant
at the university, gave a talk
about OpTiMSoC, the “Open
Tiled Manycore System-on-Chip”
framework (www.optimsoc.org).
This is a pretty complicated topic,
but essentially it lets you work with
building blocks, such as CPU cores,
Most of the talks were very technical, but there was plenty of opportunity to ask questions and learn more.
memory chips, I/O modules and
other bits ’n’ bobs, and plug them
together to create system-on-chip update on toolchain support for hardware. Indeed, one attendee
designs. Like OpenRISC, OpTiMSoC OpenRISC – that is, the current grumbled that the breaks between
is primarily created in the Verilog state of GCC, Binutils and LLVM/ presentations were too short,
hardware language, though it’s not Clang. And Sebastian Macke because everyone was enjoying
intended for production purposes. demonstrated his fascinating meeting other people and having
JavaScript emulator for the chip, one-on-one discussions! Of course,
Open hardware which lets you boot a fully working the free beer during the day helped
Meanwhile, Olof Kindgren and Linux-on-OpenRISC installation in that respect too.
Stefan Kristiansson gave updates inside your web browser.
on the status of the OpenRISC Various other talks and
project, specifically the OR1K core; presentations were given TELL US ABOUT YOUR LUG!
they talked about plans for the (see http://tum-lis.github.io/
future, such as a new execution orconf2014 for the full list), and We want to know more about your
pipeline and improved 64-bit chips. although it was a fairly small event LUG or hackspace, so please write
to us at lugs@linuxvoice.com and
Simon Cook from Embecosm, an with around 40 people turning up, it
we might send one of our roving
embedded systems company that was great to see so much passion reporters to your next LUG meeting
sponsored the conference, gave an and enthusiasm around open
16 www.linuxvoice.com
LUGS NEWS
PyCon Ireland 2014
Josette Garcia is surprised not to see Google sponsoring its local Python event…
P
yCon Ireland gathered 300 very happy to hire qualified
of Ireland’s best and foreigners.
brightest Pythonistas The first talk was “The Real
together to share knowledge, Unsolved Problems in Data
develop their skills, discuss with Science”, given by Ian Ozsvald.
peers and hopefully have some fun. According to Ian, data science was
We should not forget the people described as “the sexiest job of the
who came from further lands – 21st century” by the Harvard PyCon Ireland started with a modest 70 delegates in 2010, but by
Belgium, Hungary, France, Business Review. All that I heard 2014 has grown to over 350 atendees.
Germany, Poland and Turkey to was, “Clean your data, clean your
name but a few. data” – nothing new or 21st century hardware to people of all levels of
For €70, you get two days of here and definitely not sexy. What is experience. With their education
talks, breakfast and lunch – new, though, is how Ian highlights team they are creating resources
corporate tickets are a little more the gritty problems and proposes and training teachers who in turn
expensive but students pay a lot ways for Pythonistas to tackle and will teach kids to start
less. As we all know, Ireland offers a solve these issues to keep Python programming at a tender age.
lot of opportunities to the big as the go-to language for practical With over 650 members, Python
high-tech companies such as data science work. Ian wrote about Ireland has had a really successful
Amazon, Apple, Cisco, Dropbox, his talk on http://ianozsvald.com year. The monthly meetups have
eBay, Facebook, PayPal, Twitter and where you can also find his slides. been very well attended with
many more who in turn offer lots of One of my favourite talks was generally no less than 50 attendees
jobs and helped the Irish economy given by Ben Nuttall – “Pioneering turning up on the night. Talks are
to grow by 3.5% this year. I had a the Future of Computing given on a variety of topics from
long chat with the guys from Education”. It is nice to see the computer science, finance, big data
Brightwater Recruitment who said involvement of the Raspberry Pi and more, with a focus on Python-
that the demand for techies was Foundation, which is leading the related technologies. Preparations
very difficult to fulfil – too many way in the computing in schools for the 6th PyCon Ireland start next
posts, not enough people. They are revolution by providing affordable month. Hope I meet you there!
Open Rights Group hack day
James Baster reports from a group using data for the power of good.
O
pen Rights Group (ORG) is are erroneously blocked. There was
a UK-based organisation a nice moment at the start of the
that campaigns on digital hackathon where volunteers who
issues. Recently they held a had been working virtually for
hackathon in London to work on months finally got to meet in
technical projects, and a small but person! This project is of course
keen crowd gathered in Mozilla’s open source.
donated office (Thanks!). Other projects worked on
Mobile phone operators and ISPs included a “Kickstarter for
now offer filters, which block sites elections”, templates to help people
that may be harmful to children. make requests for their personal
The Open Rights Group
The problem is that no-one knows data, and tools for making people understand issues like tracking and used the hack day to put
which sites are filtered and the aware when they are in areas encryption to get her back. some of its ideas into
filters aren’t perfect and often block covered by CCTV or other tracking. Open Rights Group needs our action.
perfectly harmless content. So ORG A calendar of campaign events is support to continue its work – Photo credit: Jim Killock
recently launched www.blocked. being tested, and a game specially check out https://www. (CC BY-SA)
org.uk, which was created by designed to teach players about openrightsgroup.org, visit your
volunteers. This project places digital issues was shown – your local meetup or join the volunteers
machines on connections so it can hacker daughter has been taken email list and get involved before
test and publicise which websites and your character has to the next hack day!
www.linuxvoice.com 17
SHOW REPORT OGGCAMP
As well as spending time with some top-class geeks,
we managed to sell a few T-shirts and mugs – which
you can now buy at shop.linuxvoice.com.
Probably the largest event of its kind in
the whole entire United Kingdom.
2014
F
irst, a little disclosure; we, along with Canonical evening events, venue and accommodation, and the
and the OggCamp community, were Gold countless other tasks and processes we don’t know
Sponsors at this year’s event – you may have about. Without these incredibly dedicated people, the
seen the adverts we ran on OggCamp’s behalf in event simply wouldn’t happen. So firstly, a huge thank
earlier issues. We did our best to promote what was you to them.
happening and all of us here at Linux Voice attended, OggCamp is an un-conference that’s free to attend,
running a stall in the exhibitors’ area, meeting lots of but contributions are gratefully received and genuinely
incredible people and drinking slightly too much beer. help make the event a success. This year it was held
The sponsorship also gave us the chance to record a at The Oxford Hotel, some distance from the famous
live podcast on the Sunday afternoon (you can listen city centre. The conference takes place over a
on LinuxVoice.com). Saturday and a Sunday, but a great number of people
We love what the OggCamp team does and why arrived on the Friday evening and converged at the
they do it. Everyone who helps is a volunteer and they local public house, The Plough Inn. The landlords
all work incredibly hard putting the event together; looked terrified at the hordes of monochrome T-shirts
from the original planning, the merchandise, dealing but dealt patiently with the introverted beer orders. It
with registration and payments, the room re- was a beautiful evening with lots of friendly faces that
organising, staging, audio engineering, lighting, could have lasted longer had we not drunk the pub dry
18 www.linuxvoice.com
OGGCAMP SHOW REPORT
and forced them to close early. Which was definitely a Just some of the
good thing, as we all needed to get to the conference blinkenlights brought by
early for a day of talks, and talking. Reading’s MakerSpace
(RLab).
Bring and buy
Our table in the exhibitors’ room was next to Mark and
Vince from Peppertop Designs (www.peppertop.
com), the immensely talented duo behind our own
Elvie comic strip. They create all their illustrations
using open source software, releasing all of their
assets under a Creative Commons licence, and this
was the first open source/un-conference they’d been As OggCamp is an
to. We have them to thank for the pen and the paper unconference, the sessions
themselves are both
we needed to write prices on our mugs and T-shirts,
proposed and voted on in
as well as the general advice we needed at an event real time.
like this.
On our left were the equally wonderful Steph and
Stacey from Ragworm (http://ragworm.eu), printing
up their own circuit boards and assorted electronics
paraphernalia. We also met with Swindon
Hackerspace. They’d brought a long an ingenious
HUGE THANKS TO TONY HUGHES FOR THE PHOTOS CC BY 2.0
Twitter to Teletype machine, whose tappings sounded
exactly like the 1980s sports results teleprinter on
BBC’s Grandstand. This relic must have something to
do with Swindon Hackspace being located in Do you have a PCB design
Swindon’s Museum of Computing, and we promised you want made flesh? Give
to pay them a visit after the current deadline receded Ragworm a bell. They also
and find out for sure. do learner kits aimed at
There were several other hacker spaces in getting electronics
hardware teaching into
attendance, including Oxford Hackspace, the Surrey
schools.
and Hampshire hackspace and Reading’s
MakerSpace (RLab). There was also a fantastic
soldering workshop hosted by OpenTRV, whose
founder, Damon Hart-Davis, gave a talk at the event.
OpenTRV is an incredibly ambitious project that’s theoretical run time of 1.5 hours, and spent a long
attempting to cut the UK’s entire carbon footprint by while talking with the various volunteers representing
10% with a rather neat and geeky solution. In the UK, Hacker Public Radio.
many of us have hot water radiators and yet they’re The high-tech online system for determining talks
normally all controlled by a single thermostat suffered a few hiccoughs, leaving attendees to the
positioned somewhere in the house. This governs quaint but far more colourful method of “Post-It Notes
whether the whole system is on or off regardless of on a Pull Down Metal Awning”. As you’d expect, there
whether you use a room or not, or whether the were many great presentations over the two days;
temperature in other rooms is below the heating Stuart Langridge talked about cross-platform app
threshold. OpenTRV is a project based on the development, Alan Pope talked about the ‘Ubuntu
installation of thermostatic regulating valves on your Phone: the story so far’, Andrew Katz about open
radiators. These talk to a server, which allows you to hardware, and while it’s difficult to believe we missed
manage when, where it, there was a reportedly
and how the heating is fantastic talk on ‘Hop
applied to your house. “OggCamp overwhelmingly Hackers’ and open
We also learnt about adelivered in positivity, hackery source beer. We also
have to give special
great idea called ‘Repair
Cafe Reading’. This is and sheer attendee friendliness.” credit to Steve Engledow
where local experts help who actually camped. At
you fix your own stuff, including bikes, tools, OggCamp. There was also an excellent podcast panel
computers, electronics, clothes and mechanical and a raffle to round the whole weekend out, leaving
things. We thought this sounded like a fantastic us all happily exhausted. OggCamp overwhelmingly
project, not just because it gives equipment another delivered in positivity, hackery and sheer attendee
life, but because it could teach a whole new set of friendliness. We just hope that the awesome
skills. We saw the HyPi – a hydrogen powered organisers have recovered enough from the weekend
Raspberry Pi – powering a HDMIPi display, with a to do the same thing next year. See you then!
www.linuxvoice.com 19
FEATURE LINUX VS WINDOWS
It’s not enough to just
be better – you have to
know why you’re better.
I
f you’re reading this, then the chances are that The list looks very different today than it would have
you’re already pretty fond of Linux. However, it’s done a couple of years ago. Some things are just as
always good to stop and look around every once great as they’ve always been (like package
in a while to take stock of the situation, and ask management and the shell interface), but others have
yourself: is Linux still got a lot better recently.
the best choice for
me? We think that the “The more we looked at it, the Obviously, everyone
will rate each area
answer’s a resounding more we realised that there wasn’t differently. For some of
yes, and this month
we’re reminding just one reason we use Linux.” you, freedom will be the
most important reason;
ourselves just why we for others, it’ll be
use Linux. security or flexibility. If you’re a gamer, programmer,
The more we looked at it, the more we realised that office worker or sysadmin, you’ll have different
there wasn’t just one reason we use Linux. It’s better priorities, but we’ve looked at areas that we think are
in loads of different ways – too many to cover fully in important to everyone. Read on and remember
one article, but we’ve done our best. exactly why Linux is the best OS around.
20 www.linuxvoice.com
LINUX VS WINDOWS FEATURE
Online
The internet is a scary place… unless you’re a Linux user.
L
et’s be honest, the internet is built on
Linux and open source. Even if you
happen to be using Windows and
Internet Explorer, if you’re browsing the web,
then really, you’re using Linux. The majority
of the servers generating the content are
running Linux, and your Windows machine
is just an output device.
It isn’t a coincidence that Linux runs the
back-end of most of the internet. The
modern web wasn’t created by big
companies, but by little companies that
dreamed big. At least two of the biggest
companies in the world today (Google and
Facebook) were started in college dorms
less than two decades ago. Small
companies like these need flexibility and
cost effectiveness, and that just doesn’t
come from large companies with complex
software licences. Three shells running on three different computers spread out across the UK. Beat that, Windows.
The bureaucracy of proprietary solutions
means that they just can’t keep up with the requiring Microsoft’s Silverlight. With the (Heartbleed and Shellshock spring to mind),
level of innovation in Linux. Whether it’s advent of HTML 5 though, more and more but these were patched quickly, and neither
featureful filesystems, advanced sites are pushing rich content through open one has had a significant effect on web
virtualisation or containers, open source standards rather than through proprietary users, since they primarily targeted servers.
OSes have led the way since the web add-ons. We shouldn’t worry too much.
became popular. This innovation has It’s not just about what you can access,
allowed companies building their servers on there’s also the issue of what can access More than the web
Linux far more flexibility in how they deploy, you. The web is a dangerous place, or so The internet isn’t all about browsing the web
and in the internet age, flexibility in your IT is some people tell say. The truth is that we’ve though. There are myriad methods for two
a commercial advantage. been using Linux for so long that we’ve computers to communicate, including FTP,
forgotten all about internet-based malware. SSH, SCP and RSync. Almost all of these
Client side Drive-by downloads, infected adverts and protocols interact seamlessly with Linux.
Now it’s true that there are a select few others attacks simply don’t bother us, not Of course, most of these protocols work
things that you can only do online if you because we use antivirus software, but with Windows too, but they’re often wrapped
happen to be using a closed source desktop because we use Linux. So far, at least this in ineffective GUIs, or you have to download
-- Adobe’s Air and Active X spring to mind operating system has proved to be far more them from a website without being able to
-- but these are getting fewer in number resilient against attacks than Windows. verify their origins (see next page). Only on
each year. Recently, the Pipelight plugin has There have been a few scares around Linux and other Unix systems do you have
enabled Linux users to interact with sites internet security on Linux recently full access to a wide range of power users
network tools out of the box.
There is no perfect OS for the internet.
Tails
Linux is more powerful and more secure,
Some of the biggest benefits of Linux come from could be used to de-anonymise it. The zero-cost while there are still a few sites that require
its flexibility, and few things show this as well access also means that it can be shared freely, Windows or OS X to run. However, when
as Tails, the live distro designed to help people copied and handed out without any restrictions. everything is balanced out, we’re far happier
securely and anonymously access the internet. Of course, Tails isn’t only great because it’s free, running on Linux.
It’s free as in zero cost. While this is always nice, it’s also great because it delivers what it promises
it’s actually an important aspect here. If tails were (a secure anonymous operating system). While it’s
built on some commercial software (like Windows), not impossible to do that with commercial OSes, TOP 3 REASONS
it’d be a security hole, as a payment almost always it is quite hard to do. The internals are locked off LINUX IS BETTER
creates a record. Especially if it’s done over the to the extent that even making a live bootable CD FOR USE ONLINE
internet using a credit card (Bitcoin could help is difficult, let alone customising it so as to make
alleviate this, but it’s still not widely used). This it anonymous. Even if they were no backdoors or 1 Servers
would enable credit card companies to track who spyware compromising your system you could 2 Security
had access to the anonymising software, and this never verify it – which is why free software wins. 3 Flexibility
www.linuxvoice.com 21
FEATURE LINUX VS WINDOWS
Desktop
You should feel comfortable in your computing environment.
W
e’re sure that there’s someone
who likes how Windows 8 looks,
but we haven’t found them.
Ultimately, the problem with the Windows
desktop isn’t that you may like or dislike how
a particular version of Windows looks, but
that you’re stuck with the desktop
environment that Microsoft thinks you
should use. Some people like traditional
desktop environments with a taskbar along
the bottom and a menu in the lower-left
corner, while other people like tiled window
managers. Some people have embraced
Gnome Shell and Unity, while others think
they’re an aberration of all that is good in this
world. It doesn’t really matter what you like
– what matters is that it should be up to you
to decide what desktop environment you Netflix now works natively on Linux using HTML 5 video. That’s one less reason to dual boot.
like, not some multinational corporation
that’s primarily interested in profit. with the other updates on your system, so can go to to download quality software
It’s not just looks that makes the Linux you (as the user) are being constantly asked and be sure of its origin. Or, at least, that’s
desktop better than Windows though. to download yet more software. And this is what it should be. In reality, Microsoft’s
There’s one thing that always shocks us without mentioning all the intrusive browser management of the store has meant that
about Redmond’s OS: the complete lack toolbars and other ad- (and spy-) ware that few software vendors have decided to use
of package management. If you want new can come bundled in these updates. it. As a simple example, we searched for
software, you have to download it from a office software. There are many good pieces
website and install it by hand. Of course, this Some progress of office software available for Windows,
means there’s also no centralised update It would be remiss of us not to mention that from the open source suites (Libre and
system: the software you download may the situation in Windows is improving. With OpenOffice), to closed source suites (Kingsoft
or may not have a mechanism to stay up Windows 8, Microsoft introduced an app and Softmaker Office) to smaller products.
to date. Even if it does, it will be out of sync store. This is a centralised place that users The results of the search were (as ordered
by the store)
One Note (Microsoft’s note taking
application).
Office Depot (A map showing the location
of Office Depot stores).
Office Evolution (A table showing which
applications have been in which version of
MS Office).
Office 365 Garage Series (A list of videos
for Office 365).
Office Academy (A tool to help you use
MS Office).
The list goes on in much the same
fashion. There’s almost nothing useful,
and almost everything is a simple wrapper
around online content. None of the useful
office software we mentioned before is
available on this app store.
Compare this to the list we got when we
put the same search term into Ubutu 14.04:
Zoho Webservices Presentation.
Zoho Webservices Spreadsheet.
Zoho Webservices Wordprocessor.
The Windows store does have some good games, but otherwise it seems woefully barren. Extra Office applications (a menu for
22 www.linuxvoice.com
LINUX VS WINDOWS FEATURE
Ubuntu Studio).
Office Worker (a game).
LibreOffice Base.
The list goes on to show the rest of the
LibreOffice suite and other useful software.
Admittedly, this list isn’t the order we’d ideally
put Linux office software in. What’s more,
the Ubuntu store is built on top of a package
manager. The two pieces of software are
often confused, but they ultimately server
different purposes. A software store (or
software centre) is a place a company can
publish software, usually accompanied by
details about the software, screenshots
and user reviews. A package manager, on
the other hand, is a system for installing
packages and keeping them up to date.
Microsoft has promised a package
manager for Windows 10. However, it won’t
have the power of a Linux package manager.
In fact, it will be little more than a command
line wrapper around install files, and so
won’t really make the situation much better. Windows 10 brings some sanity back to the Windows desktop after the clusterfail that was
Windows 8, but users still only have one desktop environment to choose from.
Gaming
Just a few years ago, if you’d dared to company that created the OS in direct using more and more advanced hardware.
suggest that Linux was a good gaming competition with many companies that Others built weird and wonderful machines
platform, you’d have been laughed at. Now, created software for the OS. However, out of old PCs with just enough muscle to
industry leaders such as Gabe Newell are this wasn’t the only factor pushing games run modern games. Even games started to
claiming this very thing. To understand why, towards Linux. become more customisable, with some
you have to look a little at the history. As games consoles were changing, so publishers actively encouraging players to
Traditionally, gaming has been done on too were regular computers. PCs became create new levels and artwork. However, on
two distinct types of machines: consoles the dominant platform, and PCs are more top of this was always Windows, and this
and multi-purpose computers. Consoles are hackable than the computer that came has become more and more locked down
stripped down computers with everything before them. You could replace the CPU, with each version. Ultimately, with a
not necessary for games removed. However motherboard, storage, or just about anything community that was used to ever-increasing
over time, the hardware differences between else in a PC with parts from a wide range of hackability and an OS that was becoming
games consoles and general purpose manufacturers. You could even build your ever more restrictive, something had to give.
computers got smaller. own from parts. The final tipping point came in 2012 when
When Microsoft released the first Xbox Valve released its Steam games distribution
console in 2001, it was really just a PC in DIY ethos platform for Linux. Since then, Valve has
a different box with a different interface. This hackability was something that PC been encouraging games makers to release
By releasing a games console, Microsoft gamers took to heart. Some people their titles for Linux.
became a games publisher. This put the relentlessly pursued ever-higher frame rates Linux is a natural choice for PC gaming.
It’s the only OS that fully supports the
hackable philosophy of PC gaming. The
Hardware support
number of games available has exploded
Unfortunately, there are some manufacturers that by kernel developers when changes are needed to in the last couple of years with three new
only support Windows. There are even some that ensure they work with the latest kernel. major sources of games (Steam, GOG and
actively hamper development of Linux drivers by Hardware drivers on Windows, however, are Humble Store), as well as the faithful stores
people in the community who want to create open developed entirely by the hardware manufacturer, that have been selling Linux games for years
source drivers. The situation is getting better, but and usually included on a disk that comes with
it’s far from perfect. that hardware. On the one hand, this is convenient,
(such as Desura).
However, this doesn’t mean that Windows but on the other hand, it means that the hardware
has better drivers than Linux. The situation is manufacturer can force you to install all sorts TOP 3 REASONS
a little complex, and there are a few things you of weird software just to use the hardware. The LINUX IS BETTER
need to consider. Most Linux drivers are part of manufacturer may also not update drivers for older
ON THE DESKTOP
the main kernel project. This means that they’re hardware for newer versions of Windows, meaning
automatically available without the user having to that you can get stuck with either a computer you 1 Flexibility
download anything additional. It also means that can’t upgrade or hardware you can’t use – both 2 Games
they’re subject to quality checks, and are updated problems that just don’t arise with Linux.
3 Hardware
www.linuxvoice.com 23
FEATURE LINUX VS WINDOWS
Power users
There’s only one operating system for those who like a little power.
M
icrosoft is as ubiquitous as x86
processors. It could even be
argued that it owes its success
and dominance to their existence, going all
the way back to 1981 when Microsoft’s
PC-DOS and MS-DOS were sold for use on
IBM PCs and non-IBM (yet still compatible)
PC clones. And while those very early
machines used Intel 8088 CPUs, they were
closely related and quickly supplanted by the
8086 as the market exploded, creating the
foundations for what is Microsoft and the
PC market today.
When you look at it this way, it’s not
surprising that Microsoft hasn’t embraced
other architectures, and the much
anticipated ARM version of Windows 8 has
done little to change this. Windows RT, as
it is known, looks and feels like Windows Linux works on all kinds of hardware, which means the skills you learn on the desktop are
8 but its transformation to ARM has more incredibly transferrable – here’s Raspbian running on an ARM-based Raspberry Pi, for example.
to do with providing something for the
tablet market, rather than new territory anyone will try and get it running on almost substantial projects that have taken a piece
for Windows developers; Windows RT is anything – from toasters to robots, games of consumer hardware and subverted its
fundamentally the Windows 8 experience consoles to weaponry, space stations to Linux kernel into a much more open and
running on slower hardware, which misses sous-vides, Linux is everywhere. Debian ambitious project. If a piece of hardware is
the point behind Linux’s incredible success has official ports for ARM, MIPS, PowerPC, using Linux, you’ve got a far better chance
on other platforms. IBM’s S/390 servers and Sun SPARC, while of being able to get access to its innards –
whether that’s unlocking frequencies in a
commercial oscilloscope (a Rigol DS1052E
“From toasters to robots, games consoles to hack), adding web access to a digital video
weaponry and space stations, Linux is everywhere.” recorder, or just putting XBMC on your
favourite ARM-based mini-PC.
Linux has never had any kind of problem the unofficial ports still include code for Development
running on non-x86 hardware, and we’re processors such as the venerable Motorola Writing code isn’t for everyone. But software
sure that’s because it’s open source. When 68000, for instance. But it’s the ARM ports development is not only vital for native
anyone can use this source code, almost that have perhaps had the biggest impact, development, it’s also vital if a platform is to
because the ARM ‘System On A Chip’ succeed as a working environment for
packaging has transformed the embedded cross-platform development. Visual Studio
market – a complete Linux PC that fits into and Microsoft’s associated toolkits actually
a tiny low-powered space, whether that’s provide a world-class development
Android on smartphones and tablets or environment just as vital to many
Raspbian running on a Raspberry Pi. businesses and corporations as Microsoft
Regardless of the architecture, if you’re Word. The use of .Net and DirectX have
using GNU/Linux, you’re using the same created industries in their own right.
underlying operating system. That means But over the last decade, open source
you can use many of the same skills you toolkits and development models have
learnt for playing media on your desktop transformed the industry. It’s not just about
to create a media streaming device that open source compilers, or the GNU toolkit,
attaches to your television. Or the same or that you can even code on a Raspberry
skills you used to install OwnCloud on a Pi. It’s about creating a shared resource –
If you think Gnome has shutdown problems, virtual private server. This also expands to something that you couldn’t have done with
look at Windows 8. Move the mouse development and the ease with which you Microsoft’s development environment 15
somewhere then click on ‘Settings’ – only then can hack your own software and hardware. years ago. Open APIs are the backbone of
will you find the fabled shutdown button. Linux is unparalleled for this. There are many the internet, whether that’s Google probing
24 www.linuxvoice.com
LINUX VS WINDOWS FEATURE
OpenWrt
OpenWrt is one of the best known custom
firmware replacements for commercial
hardware (and even the Raspberry Pi), as it
replaces the default operating systems for
many standard routers. This is a vital job, not
only because it adds a layer of trust that only
open source audited code can provide, it also
adds features often restricted to far more costly
devices. There’s an SSH server, for example,
which is very handy when it’s built into your
router, as it enables you to create simple VPN OpenWrt started life on Linksys’ original
tunnels to your network, and there are many WRT54G (the later WRT54GL show here), and
other packages that can be installed, much like used the GPL code released by Linksys [image:
you can with a regular Linux distribution. But
CC BY-SA Vidarlo ENWP]
even in a commercial setting, OpenWrt is used
to replace enterprise-grade hardware costing This couldn’t have happened any other way, and it’s
The Windows Explorer file manager can also be
£1,000s, even if it’s just to use the traffic not even the only time this happened with wireless
replaced, but because most users don’t bother, shaping features of the new firmware. And all routers. Another custom firmware, dd-wrt, is also
your options are limited. of this is thanks to Linux being open source and available for certain Linksys models and offers a very
because Linksys had to release its own firmware similar feature set, and there are even more choices
your emails for advertising potential, or for when it was built upon the original GPL code. for other hardware platforms/routers.
the latest responsive web frameworks.
Linux is at the heart of this. It’s the native
environment for web site creation, and with finally changed with Windows 7 when the context of the data you’re working with. It
IDEs like Eclipse, the native environment for ‘Power Shell’ became an integrated part works brilliantly with Microsoft’s object
many kinds of cross-platform development of the update. PowerShell is a much closer models and is a highly useful extension to
too. And what’s more important is that with approximation of the Linux command the latest version of Windows.
many computing curriculums changing to line, and has succeeded in becoming an But it’s not a Unix shell. For example, tools
focus more on programming and hacking essential too for Windows sysadmins. such as Emacs or Vim were designed to
your own hardware, the combination of There’s even an update for Windows 10, in maximise the Unix-alike environment they
Linux and something like the Raspberry Pi the form of keyboard shortcuts. But it’s still a were running in, and it’s the same for the
is unbeatable. It’s the best kind of lock-in, vastly different beast to the Linux/Unix shell. vast majority of tools you can run from any
because we’re getting the next generation of command line. You can still perform any
coders exposed to open source and Linux, It’s about choice… task on your computer from the command
and once you’ve experienced that freedom, Most importantly, with Linux you have a line, regardless of the GUI environment you
it’s very difficult to move to a development choice. Bash is installed by the majority of might have installed. PowerShell isn’t trying
environment that offers less. distributions, but every user is free to change to compete with that functionality, which
The command line is still simply the their default command environment, or means Windows is still missing out.
easiest way to perform many kinds of tasks. change whenever they want, as each shell Which brings us to another point. With
But in its attempt to distance itself from does things differently. PowerShell could or Linux, you’re never forced to upgrade, or
the old DOS days, and to emphasise the should be another one of those options, have an application force an upgrade,
point-and-clickiness of Windows, the DOS because it’s actually good at some very or be left with files that don’t load into
prompt became a 90s relic. After being Windows/Microsoft specific tasks. It’s anything you can’t afford to buy. And
in development for a couple of years, this excellent at piping output and keeping the many proprietary formats change from
one version of an application to another,
meaning you’ll need the same version of
Photoshop, or the same version of Word, to
get the same data when you share a file.
This just doesn’t happen with open source
because the emphasis is always on open
standards and interoperability – it’s why, for
example, LibreOffice supports many more
formats that Microsoft Office.
TOP 3 REASONS
FOR POWER
USERS
1 Hackability
2 The degree of control
3 Choice
PowerShell is a great addition to Windows. But it’s not a replacement for the Unix mentality of Bash.
www.linuxvoice.com 25
FEATURE LINUX VS WINDOWS
Interoperability
Can’t we all just get along…
M
icrosoft Windows is and always
has been widely used in business.
And this isn’t likely to change.
Many companies, especially older ones,
have a long history with the software, its
capabilities and its licensing. And
companies don’t like change any more than
the users do, especially when Microsoft
does create rather good business software.
Ignoring the usability and graphical
overhauls, Windows is a perfectly good
operating system when you need to get
things done, and ignoring the cost, there’s a
good reason its business-focused
applications are the backbone of its
business. They’re industry standards
because they work well.
But there is a change coming, and it’s
one we think Microsoft is going to find
increasingly difficult to attack. As the
desktop becomes less important, and users
now have more than one device, more
than one machine, and more of one way The Free Software Foundation is running a campaign to highlight the free alternatives to Adobe’s
of working, issues besides functionality default PDF reader and icons – that’s why we’re supporting their use on LinuxVoice.com.
and performance become more relevant.
In particular, open computing and data and openness remains relevant. By getting of an open source licence, and continuing to
standards are finally being recognised other people to use Linux, you’re keeping develop – usually with a different emphasis,
as being important, after decades where this forward open momentum going. It’s or maintainer, or community. The ability to
proprietary formats have ruled in local the same reason Microsoft fought so hard, do this is enshrined within open source, and
government, health and education. and succeeded, to ratify its own Office Open it’s completely different to the closed and
In the UK, for example, government XML format, despite an open format (ODF) proprietary development model of
documentation in its static form has to already existing. It needed its own formats companies like Microsoft and Apple. To the
be provided as PDF/A, which is an open in place in order to control the way people greatest extent, they view their code and
format that can be read by lots of different shared documents created and edited with their software as their intellectual properly,
and increasingly, they’re not selling us an
application, they’re selling us the licence to
“After decades, open computing and data standards use their property for a period of time.
are finally being recognised as important.” Forking has resulted in lots of duplicity
and choice, which isn’t always a good thing.
But it means that if users don’t like the way
kinds of software. In Switzerland, the open its own software, regardless of whether Ubuntu is going, they can create a fixed
source community has just crowdfunded that meant the format was open or not. version of Ubuntu. It will either thrive or fail
approximately €8,000 to pay for LibreOffice And of course, it was always going to be in depending on whether other users agree,
developers to add digital signatures to Microsoft’s best interests to do so. There’s and that’s why we have distributions like
PDF/A documents. This is a requirement nothing wrong with that – it’s the best Mint. It also safeguards the software –
for PDF documents to be legally binding, possible way of safeguarding its business LibreOffice is a fork of OpenOffice.org, created
and is another great step towards making interests. But when open standards make when the future of the original project was
digital documentation and facilities all of our lives easier, Microsoft’s stance isn’t unclear. X.org, the display system used by
available to as many people as possible always going to be in our best interests. most installations, is a fork of XFree86, from
(the campaign is still accepting money a time when development had stalled and
until the end of the year: http://wilhelmtux. To fork or not to fork other operating systems were advancing
ch/?MID=11&PID=93). Another more tangible advantage that Linux quicker than Linux.
Of course, none of this has anything has is the power to fork the operating It’s a completely different kind of
to do with Linux specifically, but by using system. Forking refers to the act of taking development, and one we think results in
Linux you are ensuring this interoperability the source code, copying it under the terms simply better software. It’s also an attitude
26 www.linuxvoice.com
LINUX VS WINDOWS FEATURE
that rails against the burgeoning patent war
of the big software creators, along with the Convergence
constant battle to keep software patents out Both Microsoft and Apple are trying hard
of Europe. to make their users an integral part of
Which neatly leads us on to education. their services, and part of this strategy is
We’re going to argue that skills learnt on convergence – multiple devices acting as one,
Linux are more transferable, and that’s why like being able to use Word on both your tablet
and your desktop. Or your tablet becoming
it’s important that educators use Linux or your desktop. There are Linux projects and
open source software. If you learn how to distributions promising to do the same, with
create digitally signed PDFs with LibreOffice, Ubuntu’s imminent phone being perhaps
for instance, you can now use LibreOffice on the best example. But another aspect to
many different types of platform and from convergence is the shared data services for Ubuntu has re-used many of the same ideas in
your device, whether that’s for the documents its desktop, netbook and smartphone versions.
many different types of computer. that you edit, the photos you take or the
applications you purchase. same services provided by Microsoft and Apple. The
Education, education, education. As with everything else, Linux differs because great thing is that your operating system won’t be
But this also works at a lower level. Many you have a choice. You may choose to run held hostage to this choice, and neither should your
educational authorities are changing their OwnCloud on a server somewhere and manage data. And you also get to choose where and when
your own shared files and devices – there are you use these services, whether that’s on your own
computing curriculums to reflect the way we OwnCloud apps that run on both Android and hacked tablet, or BusyBox running on a NAS device,
now use computing and to hopefully iOS devices, so this works even with mixed or a router with a custom firmware. And we think
emphasise the need for computing science. hardware. Or you can even choose to use the that’s the best definition of convergence.
This September in the UK, for example,
marked the start of a new curriculum that
throws out much of the style curriculum. Or them how to code,and how to create their likely to be why the Raspberry Pi has been
in the words of the UK’s Education Secretary own programs; not just how to work a such a success, and why it uses Linux as
at the beginning of the year, “ICT used to computer, but how a computer works and the default operating system. It doesn’t
focus purely on computer literacy – how to make it work for you.” matter that it’s Linux, just that it enables you
teaching pupils, over and over again, how to to do whatever you need to achieve a
word-process, how to work a spreadsheet, Tomorrow belongs to us specific educational goal.
how to use programs already creaking into There’s only one operating system we can
obsolescence; about as much use as think of that teaches “how a computer TOP 3 REASONS
teaching children to send a telex or travel in works and how to make it work for you, ” and LINUX WINS AT
a zeppelin.” that’s Linux. Better though, is that these INTEROPERABILITY
He then explained how he wanted it skills won’t lock you into Linux. They’ll give 1 Standards compliance
to change, “Our new curriculum teaches you a lifetime of perspective whenever you 2 Education
children computer science, information use technology, whether that’s a cash 3 Convergence
technology and digital literacy: teaching dispenser or the latest Macbook Pro. This is
TWELVE REASONS WHY LINUX WINS TOP 3 REASONS LINUX
You knew it was a forgone conclusion. IS BETTER FOR . . .
A
USE ONLINE
fter all that, it feels like we’ve only our comparison has become 1 Servers
scratched the surface. What’s more ‘heuristic’ for a good reason; 2 Security
also interesting is how things have technology is now shaping almost every 3 Flexibility
changed. Ten years ago we may have aspect of our lives and it’s no longer about
started a comparison like this as a feature- one company or operating system. It’s about USE WITH LINUX
by-feature comparison of the two operating your data, control, freedom and choice, and 1 Flexibility
systems, as if the desktop was the only way these are ideas that don’t align with our old 2 Games
3 Hardware
one operating system could ever come to way of thinking.
dominate over another – or win, as we’d They’re also ideas that we feel strongly
have put it at the time. Many of us still use about, which naturally leaves us with only POWER USERS
1 Hackability
Windows, and it still does a great job in the one choice of operating system. We know
2 The degree of control
millions upon millions of places it’s installed we’re preaching to the choir when we say 3 Choice
and used. It’s a huge accomplishment and Linux wins in so many different ways, but it’s
a testament to the skills of the corporation important to remember why, and just why
INTEROPERABILITY
behind it. GNU, Linux and Free Software are getting 1 Standards compliance
But side-by-side comparisons are no stronger and more relevant with each 2 Education
longer relevant. We hate using the word, but passing decade. 3 Convergence
www.linuxvoice.com 27
FEATURE RASPBERRY PI A+
TOP MARKS FOR
RASPBERRY PI
Russell Barnes speaks to the founder of the
Raspberry Pi Foundation to find out why he thinks
the Model A+ is their most exciting release yet…
A+
E
ben Upton came up with the idea of an computers for kids and we started putting some
affordable credit card-sized Linux PC while thought into what we could do about it.”
working as the Director of Studies in Computer As he talks Eben brandishes the latest offering in
Science at St John’s College, Cambridge. Part of his the Raspberry Pi line-up, the Model A+. It looks rather
role was to manage and different to its
monitor undergraduate predecessors, almost as
admissions, something “The model A+ looks as if if someone’s taken a
Cambridge appeared to
be fast running out of.
someone’s taken a hacksaw hacksaw to a Raspberry
Pi and lopped an end
“It wasn’t a case of me to a Pi and lopped an end off.” clean off. As it turns out,
waking up one day that’s almost exactly
wanting to make a credit card-sized computer, but what happened, but there’s a bit more to the story
waking up one day and realising we’ve got no than that…
computer science students and wondering why,” For a start, this isn’t the first time the Raspberry Pi’s
explains Upton. “Ultimately we came to the conclusion winning formula has been tweaked. Earlier this year
that there was a distinct lack of programmable the Foundation launched the B+, an improved version
28 www.linuxvoice.com
RASPBERRY PI A+ FEATURE
Eben Upton: Quickfire Q&A
What’s your favourite thing about Does the $20 make the Pi more of massive gulf between the two products.
the model A+? an Arduino competitor?
It’s amazing what ergonomics can We’re just about in the range of Will the Raspberry Pi Compute
do for the popularity of a product. official Arduinos in terms of price. Of Module ever take off with
One of the things people love about the B+ course we’re not an Arduino competitor. I industrial partners?
is the fact it looks nice. It’s got the rounded don’t think there’s a great deal of overlap We don’t want to push people to the
corners, the mounting holes and the between what the Raspberry Pi is the right Compute Module until they’re ready.
connectors are all lined up with the edge of product for and what the Arduino is the I think the Compute Module is well suited
the board – it’s just nicer. right product for. The Arduino still to industrial solutions, so if someone
I’m really obsessed with the rounded consumes less than power than an A+ and needs 10k of something it’s definitely
corners [laughs]. It’s a little thing and it’s it has analog inputs. The Raspberry Pi on worth doing a small amount of R&D so you
really easy, but it makes such a difference the other hand drives a display and has can go for a Compute Module, but it takes
on the A+. more processing power. There’s still a time to make that transition.
of its 3.5 million-selling Model B. It’s the board Upton overnight. “Even though it was only a couple of weeks
refers to as the ‘deluxe model’, because while the from when the B+ came out, we sold more Raspberry
Model A is the Foundation’s affordable flagship Pi Pi’s in that half of July than we’ve ever sold in any
priced at $25, the B comes with the added single month before,” enthused Upton. Today the
convenience of extra USB ports and Ethernet Raspberry Pi is selling over 100 thousand per month
networking for an extra $10. The dream was to and the Foundation is on the brink of selling its four
produce a $25 computer powered by open source millionth Linux-powered PC.
software, but it seems the vast majority of geeks and
educators were more than happy to pay an extra ten Do we need a Model A?
bucks for the privilege. With the Model A selling less in its entire lifetime than
Thanks to the massive success of the Model B, the the Model B sells in a month, it wouldn’t be outside the
team employed by the charity has positively ballooned realm of reason to wonder if the Model A line is worth
over the last 12 months (even so the entire workforce
can be counted on two hands and one foot). One of
those new employees was Director of Hardware, Original Model B goes back into production
James Adams, who was tasked to taking over from
The old Model B is once again rolling off the “After putting the B+ out there what we
founding member Pete Lomas to create the production line at Sony’s facilities in Wales. found was that a lot of people who were
Raspberry Pi Plus line. “Obviously when we started the Model B+ putting the model B into their products were
With a combination of user feedback and raw we wanted to make sure our channel saying, ‘actually we’re pretty happy with the
common sense, Adams utilised the new economies partners weren’t stuck with lots of Model B,” Model B, can we keep buying it?’. It’s great
says Upton. “We’ve got a lot of small that we’ve got industrial customers that turn
of scale and reputation the Foundation had achieved
businesses that started around the Pi and if around and ask for 10,000 more Model Bs.”
to really go to town with the Model B+ improving the you leave them with lots of old inventory it But what about the original Model As?
board layout, adding more General Purpose Inputs & could cause them lots of problems. We told “We’re definitely not going to make any more
Output (GPIO) pins, doubling the number of USB ports them all about the B+ and made sure they As. Industrial demand for As hasn’t been
and massively improving power consumption among could move their old stock before we put the anywhere near as strong, so I really don’t
B+ on sale. want to restart the A line.”
other things. And all this happened at the same retail
price as the original Model B.
It was just the ticket too. The B+ became the fastest
selling credit card-sized PC in the world almost
The key benefit of the Model A+ isn’t just the low price –
it’s the low, low power consumption.
www.linuxvoice.com 29
FEATURE RASPBERRY PI A+
model since it’s only an extra $10,” explains Upton. “I
feel like some people missed out on why the lower-
power model like the Model A can make sense. If
you’re building something with robotics, or essentially
any project that doesn’t need Ethernet networking, it’s
a great fit.”
Eben also thinks it would make a mockery of the
original $25 computer promise if they didn’t continue
with the Model A: “It’s also really important to us
because it’s our flagship product. It was our original
stake in the ground and where it all started.”
Chopping the end off the B+
While some tech firms would be nervous to have
another try at a less successful model, the Foundation
is very excited about the release of the A+. A look over
the specs shows it’s a big improvement over the
flagship Raspberry Pi, but the groundwork for the A+
started when the B+ was still the drawing board.
Upton says: “James Adams came over to see me
[with a Model B+] and said ‘you know we can chop the
end of this board off, right?!’”
Check out those corners –
continuing at all. Indeed, the $25 credit card-sized PC It transpired that Adams actually designed the
see how round they are.
for schools is barely in any schools, despite there Model B+ with the Model A+ in mind, making it a trivial
being a good number of more expensive Model Bs to board design tweak to shave quite a large amount off
be found in the education sector. one end of the board for the A+.
As it turns out, it’s only really hardcore hackers that “Where the original Pi had ad hoc mounting hole
make any real use of the Model A. People like Dave positions, the B+ has these nicely positioned square
Akerman (www.daveakerman.com). Dave regularly mounting holes on the body of the board, then an
attaches Model A Pis to weather balloons so he can extension on the right that contains the Ethernet and
take pictures with the Camera Board from an altitude USB ports, which are ‘outboard’ of these mounting
of around 35km – right on the edge of space. With holes,” continues Upton. “James basically explained
projects of this magnitude every milligram and that we can chop the board off at the mounting holes
milliwatt really count and the Model A’s lighter load in and find room on the board for a single USB
terms of weight and power consumption makes it the connector, meaning we could make an A+ board that
ideal candidate. was markedly smaller than the B+.”
Eben is the first to admit the Foundation failed to It certainly feels impressive in your hands. The
communicate the benefits of the Model A beyond its mounting holes are in the same place as the B+, but
cheaper price, and it’s something the team are with the shorter board they’re located in all four
determined to rectify with the new Model A+. corners, making it a shade off being totally square.
“It’s easy for people to look at the Model A and think Since it has the same improved GPIO as the B+, it’s
it’s just a cheaper variant of the B. When they look at it also still compatible with the new Hardware Attached
like that they might as well just go for the deluxe on Top (HAT) standard for Raspberry Pi add-on
boards. In fact, the outline of a Model A+ and a HAT
board is identical, making an A+ with HAT a very
Model A+ essentials
compact and mobile combination.
With only one USB port, getting by with a Touchpad – £26 (www.thepihut.com) “We set about making a mock-up of the design and
Model A with anything more than an SSH This tiny wireless keyboard with touchpad we all agreed that it made a really quite attractive
connection over Wi-Fi can be tricky. Here are will give you decent control over your Model
a few add-ons designed to help… A+ with a full qwerty keyboard, a built-in
product,” continues Upton. “It really adds something to
Broadcom WiFi adapter & 2 port USB hub touchpad, backlit keys, multimedia controls the mix and it adds something to its uniqueness too.
– £9.99 (www.pi-supply.com) and even an integrated laser pointer. It’s cheaper than the B+, it consumes less power, but
The fact that the drivers for Broadcom’s USB sound adaptor for Raspberry Pi now it’s quite a bit smaller too.”
range of Wi-Fi adapters have only just – £3.99 (www.modmypi.com) Not jut smaller in the X dimension either – it’s
appeared in the Raspberry Pi’s official distro, Want to use your Model A+ as a decent
Raspbian, is a minor embarrassment, but audio player or a voice recorder? Although
almost half the height too. Until it was replaced in the
perhaps by way of making up for the the A+ and B+ have improved audio support, Model B+ by a dual-purpose 3.5mm audio and
oversight you can now buy this two-port USB there’s no microphone input and the audio it composite jack, the Raspberry Pi’s board height was
hub with built-in Wi-Fi. OK, it’s not going to outputs is still low-definition. The only way dictated by the massive (not to mention bright yellow)
win any awards for design, but you can use it around either of these problems is to use a composite video port. Now the limiting factor on the
turn your Model A+ into B+ at a whim. USB audio card, like this affordable little
Riii Miniature Wireless USB Keyboard with fellow from ModMyPi.com.
height of the board is the low-profile USB port, bringing
the Z dimension down from 21mm to 12mm.
30 www.linuxvoice.com
RASPBERRY PI A+ FEATURE
Side by side How the Model A+ and B+ stack up
Model A+ specs Expansion: Model B+ specs Expansion:
Price: ~£15/$20 1 x Micro SD card slot Price: ~£27/$35 1 x Micro SD card slot
Dimensions: 65 x 56 x 12mm 40 GPIO pins Dimensions: 85.6 x 56 x 21mm 40 GPIO Pins
SOC: Broadcom BCM2835 (700MHz) 1 x USB port SOC: Broadcom BCM2835 (700MHz) 4 x USB ports
Memory: 256MB RAM Power consumption: Memory: 512MB RAM Power consumption:
Networking: None 200mA under load Networking: Ethernet 10/100 370mA under load
(left, Model A+; right: Model B+)
Like the Model A, the A+ features just one USB port, possible to make. That said, the Foundation hasn’t
256MB RAM and no Ethernet port. Besides this (and rested on its laurels with the A+. In fact, they ripped up
the size of the board) Eben says it’s ‘electrically their own ‘$25 computer’ rule book.
identical’ to the Model B+. This means the A+ now “I had a great conversation with [Google boss] Eric
benefits from the B+’s improved power chain, Schmidt last year when Google gave us a large
meaning you don’t need the mother of all micro USB donation to help us distribute Raspberry Pis to school
power adaptors to keep your Pi running or a powered children,” says Upton. “We had a really good
USB hub to enable the use of USB storage. On top of conversation and we were talking about price and
that, if you’re looking to run a project from batteries performance among other things and he said to me
you’re in for a massive boost in longevity. ‘try and be as cheap as possible… try and get as close
We’ve yet to put the Model A+ through the wringer to free as you can.’
on a benchmarking test bed, but we know it draws “I found it really inspirational to have someone like
about 200mA from the 5V power with a keyboard Eric not just say ‘well done; you’ve got a great product’,
plugged in, running ‘hello_teapot’ over a HDMI monitor. but ‘why aren’t you asking yourself how to be
Compared to the already impressive 370mA from the cheaper?’”
Model B+ it’s head-turning stuff. It wasn’t long until the Foundation ran off the
prototypes of the board and he and the team really
The $20 credit card-sized PC took to the new design. “It’s just a great product,”
The Raspberry Pi Foundation has always been exclaims Upton. “I almost don’t care how many of
ambitious when it comes to price, and the A+ already these we sell. The A+ went from something we knew
just about the cheapest single-board computer it’s we had to do to something that we’re actually really
enthusiastic about.
“It gives people a really low-cost way to come and
play with Linux and it gives people a low-cost way to
get a Raspberry Pi. We still think most people are still
going to buy B+s, but it gives people a way to come
and join in for the cost of 4 Starbucks coffees.”
According to Upton they’re really bumping up
against the limits of how much you can build a
significantly high-tech product for and not have
people lose money in the process.
“It’s already about the cheapest thing you can get
HDMI out, and the potential it brings for displaying video that does this kind of thing by some margin, but we’ll
to your television, is a strong factor in favour of the Pi. never be complacent about that,” he concludes.
www.linuxvoice.com 31
SOFTWARE LITIGATION
LITIGATION VS
FREE SOFTWARE
A flurry of patent lawsuits has affected
the landscape for open source software
developers and businesses operating in the
United States. Adam Saunders examines
the state of play.
T
he United States is a popular region for patent relating to Android. The patents covered a variety of
litigation for a few reasons. There are some areas, including one that could read on natural
courts, such as the Eastern District of Texas, address translation, one that could read on
that have earned a reputation for being “plaintiff- notification shades in mobile devices, and one for
friendly” when it comes to patent cases. That is, if GUIs to handle VPNs. For example, the drop-down
someone brings a patent infringement lawsuit there, shade that the user pulls down on Android phones
they’re more likely than not to win it. The payouts are and tablets to check your notifications implements
also pretty high in the United States for a victorious ideas that Rockstar claims to own.
plaintiff; awards can be in the hundreds of millions of Google fought back in December 2013 to try to get
dollars, with the highest award given weighing in at the case pulled out of the plaintiff-friendly Eastern
over $1.6 billion (US). District of Texas and switched to the Northern District
As an individual admitted to practice law in my of California, by requesting a declaratory judgment of
jurisdiction (Ontario, Canada) and an open source non-infringement. That is, asking the California court
enthusiast, I have the background in the English to declare that Google isn’t infringing. After almost a
common law system (a basic foundation shared by year, and a formal request made to the US Court of
most English-speaking countries) to analyse and Appeals for the Federal Circuit, Google did manage to
understand these cases. get the case switched to California from Texas; a
major victory.
Rockstar v Google et al Huawei settled confidentially with Rockstar in
A ruling in this case could chill commercial efforts January 2014. Samsung, HTC, ASUS, LG, ZTE, and
around the open source Android operating system. Pantech would fight on; they moved to get the suit
Rockstar dismissed on a
Consortium Inc., a jurisdictional
non-practising patent “Rockstar’s business model is technicality.
holding company
(sometimes known as
based solely on extracting money The Northern
District court ruled in
patent trolls) owns a from patent licensing deals.” April in favour of
large number of Google’s motion to
patents. Rockstar was move the jurisdiction
formed by a group of major IT corporations including there. But the Eastern District of Texas court refused
Apple, Blackberry, Sony, Microsoft, and Ericsson to to accept this, so Google asked the Court of Appeals
buy patents collectively as part of an auction of the for the Federal Circuit to move the case to the
Nortel Networks bankruptcy sale in 2011. Nortel Northern District.
Networks was a Canadian telecommunications With Rockstar’s business model based solely on
corporation with operations around the world, making extracting money from patent licensing deals or
routers, computer hardware, and software. Over its lawsuits, this lawsuit may go on for years to come.
lifespan, it filed for thousands of patents relating to its We’re still waiting for the technical merits of the case
work. to be assessed! Open source developers should follow
In late 2013, Rockstar sued essentially all the major this case, as the results may encourage or
Android phone and tablet OEMs, including Samsung, discourage commercial development of Android-
Huawei, ASUS and Google for patent infringement based devices.
32 www.linuxvoice.com
SOFTWARE LITIGATION
Octane v Icon and Highmark v Allcare
The rulings in these cases dealt significant damage to Copyright litigation to watch:
patent trolling in the United States.
As well as patent action, there’s been some issue in this case. It wants the Supreme
The issue in Octane – a battle between two fitness recent copyright litigation affecting open Court to answer this question: “Whether
equipment companies over patents on elliptical source, particularly Oracle v Google. Oracle copyright protection extends to all elements
machines – was the standard by which a “court in sued Google for patent and copyright of an original work of computer software,
exceptional cases may award reasonable attorney infringement relating to Google’s use including a system or method of operation,
of Java in Android (Oracle acquired the that an author could have written in more
fees to the prevailing party.” The Supreme Court of the
Java copyrights when it bought Sun than one way.”
United States held unanimously in favour of the Microsystems, which created Java in 1995. If the Supreme Court hears this case,
plaintiff, Octane, to the benefit of those fighting This litigation has been going on for a couple it’ll affect not only open source software,
against patent trolls. years now, with an appeals court ruling that but the freedom of all software developers
Supreme Court Justice Sonia Sotomayor, who Application Programming Interfaces (APIs) working in the United States or for the
can be subject to copyright. American market. If the court says that such
wrote the decision for the court, began by tracing the
In early October of this year, Google protection does extend, then we could see
history of the rules for attorney’s fee awards in patent formally applied to the Supreme Court to ask sharp limits on third-party developers trying
litigation. The most recent change to the rules, Section that they hear an appeal on the copyright to reimplement APIs of all sorts.
285 of the Patent Act, essentially inserted two words
— “exceptional cases” — into those rules. Sotomayor
noted that the Supreme Court of the United States This ruling will weaken patent trolling, as it gives
had previously ruled that those two words merely much more leeway to the lower courts to throw out a
clarify the rules: patent case if they suspect a troll. By making appeals
Following the addition of an appellate court for all less attractive for trolls, it lowers the chances of them
patent matters in the US — the Court of Appeals for dragging out litigation, making them much less
the Federal Circuit (CAFC) — in 1982, the status quo threatening to potential victims.
was largely upheld for over 20 years; that is, “the The Highmark case dealt with how much deference
Federal Circuit [...] instructed district courts to consider appeals courts should give to district courts that
the totality of the circumstances when making fee award attorney’s fees in patent infringement cases.
determinations under §285” (page 5). But when the Speaking again for a unanimous SCOTUS, Sotomayor
CAFC came across a particular case nine years ago ruled, in light of the Octane decision, that there should
— Brooks Furniture vs Dutailier — it decided on its own be considerable deference given to the lower courts:
to implement a new standard: a defendant could only “[Section]285 commits the determination whether a
get attorney’s fees if the lawsuit was done “in case is ‘exceptional’ to the discretion of the district
subjective bad faith and [...] [it was] objectively court [...]” (page 4). This effectively means that a
baseless (page 8). higher court reversing an award of attorney’s fees will
The Supreme Court has now cast aside that become quite uncommon; a significant disincentive to
restrictive standard. After looking at dictionary potential patent trolls.
definitions of “exceptional”, SCOTUS decided on this
standard:
That an ‘exceptional’ case is simply one that stands
out from others with respect to the substantive
strength of a party’s litigating position (considering
both the governing law and the facts of the case) or
the unreasonable manner in which the case was
litigated. District courts may determine whether a
case is ‘exceptional’ in the case-by-case exercise of
their discretion, considering the totality of the
circumstances. (pages 7–8)
What is the ITC?
The International Trade Commission (ITC) is an American
administrative body that handles complaints about unfair
competition in international trade as defined by law. One
type of unfair competition that it can issue administrative
rulings against are products made from competitors,
imported from abroad for sale in the USA, that infringe
The US Supreme Court
one or more patents. One remedy that the ITC can award
may seem remote to non-
to successful complainants is a ban on the importation
of those infringing products. While it does not have the Americans, but the US is
authority to award damages (ie money), combining an ITC such a huge market that
action with a lawsuit seeking damages can be a powerful its decisions affect us all.
legal attack against a competitor. Photo by yeowatzup CC-A
2.0 Generic.
www.linuxvoice.com 33
SOFTWARE LITIGATION
of exchanging obligations (the media claims)” (page 3
of the ruling).
Thomas then goes on to cite the court’s recent
ruling in Mayo vs Prometheus, which established a
test to determine which inventions incorporating
abstract ideas are patent-eligible: “First, we determine
whether the claims at issue are directed to one of
those patent-ineligible concepts” (page 7). If it is so
directed, then the court looks at “the elements of each
claim both individually and ‘as an ordered
combination’ to determine whether the additional
elements ‘transform the nature of the claim’ into a
patent-eligible application” (page 7). This is what
Thomas refers to as “a search for an ‘inventive
concept’” (page 7).
The court then applies this “Mayo test” to Alice’s
patents. Beginning with the first step of the test,
Thomas notes that these patents do incorporate an
Google also bid on the
Nortel Networks patents,
Alice v CLS abstract concept, as “these claims are drawn to the
but lost out to Rockstar, Alice Corporation, a non-practice patent-holding entity, abstract idea of intermediated settlement” (page 7).
which bought them for held patents on a method, system, and process for a Thomas cites previous Supreme Court case law,
$4.5 billion (US). Photo: particular type of financial risk hedging: namely, that emphasising its ruling in Bilski v Kappos (another
Kenneth Lu, CC-A 2.0 one party to a set of financial transactions won’t pay case, which threw out a patent on financial risk
Generic. at one or more stages in the set. This risk is known as hedging), as illustrating examples of other patent-
“settlement risk”. Alice’s patents describe using a ineligible “inventions”. Intermediated settlement is an
computer to keep track of the transactions between old, abstract financial idea: “Like the risk hedging in
the parties. If the computer determines that a party Bilski, the concept of intermediated settlement is ‘a
does not have sufficient funds to pay their obligations fundamental economic practice long prevalent in our
to the other side, then the transaction is blocked. system of commerce’” (page 9).
Litigation against CLS Bank International for alleged Thomas then applies the second step: looking at
infringement of these patented ideas started in 2007, what else is in the patent claims to see if there’s
eventually winding its way up to the Supreme Court of anything more to Alice’s “invention” than this abstract
the United States. idea. The method claims don’t pass the court’s test
Writing for a unanimous court, Supreme Court because they “merely require generic computer
Justice Clarence Thomas begins with a brief implementation” (page 10). In what might be the most
description of what the patents claimed. There are important part of the ruling, Thomas emphasises that
effectively three different types of claims made: “(1) while some inventions involving computers may be
the foregoing method for exchanging obligations (the patent-eligible, just because a computer is used as
method claims), (2) a computer system configured to part of an “invention” is not, on its own, enough to get
carry out the method for exchanging obligations (the a patent out of an abstract idea (pages 13–14):
system claims), and (3) a computer-readable medium There is no dispute that a computer is a tangible
containing program code for performing the method system [...] or that many computer-implemented
claims are formally addressed to patent-eligible
subject matter. But if that were the end of the
Post-Alice software patent cases [Section]101 inquiry, an applicant could claim any
principle of the physical or social sciences by reciting
There have been a number of software which described using computers to
a computer system configured to implement the
patents rejected by lower and appeals courts communicate automatically with
for invalidity in the wake of the Alice vs CLS individuals to see if they are completing an relevant concept. Such a result would make the
judgement. Here’s a look at three of them: assigned task. This was challenged in determination of patent eligibility “depend simply on
1 Comcast vs Sprint. (United States District court by McKinley, a warehouse and the draftsman’s art” [...]
Court for the District of Delaware) loading company and a defendant they The remainder of the patents, which are the system
Comcast’s patent claim it launched sued. The patent was rejected as invalid
and media claims, didn’t hold up either. Alice argued
against Sprint Communications described for being a mere abstract idea.
asking a telephone caller if they’d like to 3 Dietgoal Innovations vs Bravo Media. that the system claims depend on a particular
make another connection. It was thrown (United States District Court for the computer hardware configuration. When the court
out on the grounds that it is “drawn to the Southern District of New York) Dietgoal’s looked at that configuration, it found only a generic
abstract, and fundamental, idea of a patent, which described meal planning as general-purpose computer. Since Alice had stated in
conditional decision.” implemented by a computer, was rejected
an earlier brief that if its method claims fail, so do its
2 Eclipse vs McKinley (United States District as invalid for being an abstract “do-it-on-a-
computer” patent and thus “drawn to media claims, the court threw out the media claims as
Court for the Central District of California).
Eclipse IP owned some patents, one of patent-ineligible subject matter”. well. Having demonstrated the court’s rationale for
invalidating Alice’s patents, Thomas conclude the
34 www.linuxvoice.com
SOFTWARE LITIGATION
ruling by upholding the Court of Appeals for the
Federal Circuit’s decision to throw out the patents. What’s the difference between patents and copyright?
Justice Sotomayor also gave a one-paragraph
A patent is a legally granted, time-limited patentee gets a commercial monopoly. Some
opinion concurring with the court, which was joined monopoly over the use, manufacture, and particular ideas can’t be patented; in general,
by Justice Ruth Ginsburg and Justice Stephen Breyer. distribution of an invention. It’s not a right things like mathematical formulas or mere
A concurring opinion means that some judges agreed to practice the patented idea, it’s a right to abstract concepts on their own.
with another opinion (in this case, the unanimous exclude others from practicing the invention. A copyright is a legally-granted, time-
While patent laws differ across the world, limited near-monopoly over a creative
opinion of the court), but that they wanted to note
there are some generalities that we can expression. This includes software (in both
another view that they had. In that opinion, Sotomayor speak of. binary and source code forms), paintings,
notes that the three of them would completely throw A patent has to be on a new, useful, music, sculptures, and novels. It’s a near-
out business methods as unpatentable. and non-obvious invention. The idea is monopoly because most jurisdictions offer
This ruling has already had an impact, leading that patents are supposed to encourage some form of “fair use” or “fair dealing”
innovation and reduce reliance on secrecy to exceptions, which let the public use these
judges to throw out several cases.
the overall benefit of the public. In exchange expressions without having to get a licence.
for a thorough description of the invention These vary by jurisdiction, but often include
NVIDIA vs Samsung et al to the public (through a patent office), the uses like parody, news reporting, or satire.
In September 2014, Nvidia launched two patent
infringement actions against Samsung and
Qualcomm. Claiming infringements of seven patents, devices, are infringing (page 3). The company also
which read on basic GPU functionality, this litigation lists Samsung products, which “include, but are not
can’t make comfortable reading for those considering limited to, mobile products such as mobile phones
opening up their graphics device drivers. (including the Galaxy Note 4, Galaxy Note Edge,
According to Nvidia, it was negotiating with Galaxy S5, Galaxy Note 3, and Galaxy S4) and tablet
Samsung for a patent licensing agreement. These computers (including the Galaxy Tab S, Galaxy Note
talks failed after Samsung blamed its hardware Pro, and Galaxy Tab 2)”.
suppliers (eg Qualcomm) for infringing, claiming no There are two separate actions here: a complaint at
responsibility themselves. Nvidia then decided to take the International Trade Commission (ITC) and a
legal action against both Samsung and Qualcomm. lawsuit in the US District Court for the District of
Nvidia wants money, but it also wants to ban the Delaware. While the ITC can’t award damages (ie
importation and sale of particular processors and money), it can stop importation of patent-infringing
devices. In its complaint to the International Trade devices and components. The lawsuit in Delaware
Commission (ITC), Nvidia has a non-exhaustive list of also seeks a ban on the allegedly infringing products,
Qualcomm products: “These processors include but seeks damages too. This double whammy is an
Qualcomm’s Snapdragon processors using Adreno increasingly common tactic in the mobile device
GPUs” (page 12). Nvidia also alleges that “Samsung’s patent wars.
Exynos processors,” which “use Mali GPUs or Those interested in timelines for these processes
PowerVR GPUs”, found in several of its mobile may not be surprised to hear that they are often
drawn-out actions. The ITC decided on 6 October
2014 that it will investigate Nvidia’s complaints. This
type of investigation could take months or years; we
will find out by the end of November when the ITC
estimates its investigation will finish. The worst
outcome for Qualcomm and Samsung here would be
a ban on importing and selling the devices that Nvidia
complained about in the United States, which is
clearly a lucrative market.
The Delaware action may also be lengthy. We can
expect time-consuming motions back and forth from
both sides. When you add on to that briefs and
memoranda, a pretrial conference, discovery,
depositions and oral arguments (not to mention any
requests for deadline extensions), a trial could easily
be a year away (if it comes to that). The worst
outcome for Qualcomm and Samsung here is a US
ban on selling the devices Nvidia complained about
along with a hefty damages payment to Nvidia.
The impact these proceedings could have might be
a further chill on graphics hardware innovation. It may
US Supreme Court Justice Sonia Sotomayor is one of a also prove to discourage companies from opening up
number of SCOTUS judges fighting back against patent their graphics device drivers, as they may fear that
trolls. Photo by Cknight70 CC-A 2.0 Generic. that would open them up to litigation.
www.linuxvoice.com 35
FEATURE LINUX VOICE AWARDS
THE
AWARDS
2015
Get involved in choosing who benefits
from our profits sharing scheme.
I
t’s been 10 months since the first issue of Linux with issue 1. Head over to LinuxVoice.com and grab a
Voice went on sale. So much has happened and it copy, if you haven’t already.
feels like we’ve barely started. But it’s not long Our third promise was to give 50% of our profits
before we reach our first major milestone (after hitting back to Free Software and Linux communities. And
our crowdfunding target) – the end of our first year. the best thing about this was that you – our readers
We made three promises during our campaign. One – get to choose who gets to benefits. And with only a
was to create the best couple of months to go
Linux and Free Software before our first year’s
magazine available, and “We promised to give 50% of accounts, now is the time
while there’s always
going to be room for
our profits back to Linux and to get started on the
process. However, we
improvement we think Free Software communities.” want the process to be
we’ve hit this target. Our as open and as adaptable
second promise was to release the entire contents of as possible. Like the magazine, we want to get as
each issue under the terms of the Creative Commons close as possible to the ideal solution, but we also
Share-Alike licence and release each issue within nine want to be open and transparent enough that we can
months of them going on sale. As this very issue improve the process with your help. Which is why
circulates the globe, that’s exactly what we’ll be doing we’re starting a little early.
36 www.linuxvoice.com
LINUX VOICE AWARDS FEATURE
Issue 1 is now yours All of our work for the first issue has been relicensed under the terms of Creative Commons
As per our promise during the Indiegogo One example of what can be done with
campaign that launched this magazine, the content is that a few of us here on the
our first issue, from February 2014, is now magazine and many from the Linux Voice
available completely free. But just like community have taken those words and
open source, we don’t mean just in the ‘free turned them into a freely distributable audio
beer’ cost sense, but also in the freedom recording. We’ve split the recordings by
sense. We always felt this was incredibly article and also made a complete RSS file
important for a magazine about free and if you wanted to grab the long play version.
open source software, and we always wanted It’s not bad for a first effort and it’s brilliant
to be a magazine that gave back in the hearing everyone’s contribution. We’re all
same way, with a similar commitment to extremely grateful for the support from the
the same principles that drive open source various people who have made their own
development. recordings (you only need a microphone and
This is also the reason why we chose the a copy of Audacity if you want to help with
Attribution-ShareAlike variant of the Creative our next issue). Not only does the audio
Commons licences. This allows you to take version make our content more accessible,
our content and copy and redistribute on we also think that the spoken version makes
any medium or in any format. Just like open an excellent time killer for long journeys and
source, you can also edit, transform and train delays. Take a look at LinuxVoice.com
build on any of our work for any purpose – for more information.
even commercially! The only conditions are
that you need to give us credit (attribution)
and document any changes that you’ve
made. And also like open source, you need Download, modify, share and
to make those changes available under the upload our very first issue, thanks
same terms. to the Creative Commons.
Central to our strategy are the 114 comments we into the selection pool. For that reason, we want to
received from our blog post “Giving Profits Back: split the process into three stages. The first stage is
Where and How”, which we put online in November going to be open to everyone who may want to
2013. As you might expect when you ask a question participate, and we’ll use this stage to formulate a
like this, there are many different points of view, many shortlist of projects that go into the second stage. The
of which may be incompatible with one another, or second stage will be the voting process where our
even have the potential to cause conflict. This is the readers will decide on which projects they’d like to see
absolute last thing we want to happen from doing succeed, and the final stage will be the awards
this, so we want to tread carefully. At least for our first themselves.
year, as we expect profits to be modest, and we can The list of potential projects out of those mentioned
fine-tune the process and set a firm foundation for in the “Giving Profits Back” story comments is huge,
future Linux Voice awards. mostly split between what we’d call organisations (24
Apart from the many specific projects, communities from the original post, including FSF, EFF, Mozilla, etc.),
and foundations that were mentioned in that original distributions (nine in the post, including Debian,
post, there was a central point that was repeated by Slackware, Crunchbang) and an enormous variety of
many: both large and small projects should benefit. individual software projects. We thought about
This was primarily because most of us agree that splitting this huge category into sub-categories –
large projects, such as the Free Software Foundation maybe one for graphical applications, another for APIs
or the Electronic Freedom Foundation, should still be or frameworks and another for desktop environments,
supported, but so too should the smaller projects, for example, but we’re guessing this would get
perhaps to help with web hosting, or to help a complicated quickly and maybe add a little
developer attend a conference. That means we’ve got unnecessary conflict when people argue over our
to split the overall contributions into different
categories, and for that, we’re going to need a shortlist
of both categories and the projects within them.
Voting process The Open Rights Group
We’ve got our own strong ideas about the kinds of has similar aims to the
projects and communities we’d like to support. We’ve EFF but UK-based and
focused on UK activism,
spoken about and spoken to many of the people and
including fighting the
communities we’d like to see, and we’ve covered a Digital Economy Act
handful of our favourites over the last 10 months. But and the default use of
it’s vitally important that our readers get to choose not content filters. www.
only who wins any awards, but also what projects go openrightsgroup.org
www.linuxvoice.com 37
FEATURE LINUX VOICE AWARDS
arbitrary categorisations. But it does seem like we balance of proposals, we’ll put the most popular 10
could make a sensible split by putting the proposals for each into the two categories, creating
organisations and the distros into one pool, and the those two shortlists. We’ll do this publicly so that
huge variety of software projects into another. This everyone can see the progress of their favourite
would allow us to reward more projects, and reward projects until we have a final list at some pre-
both big and small at the same time – depending on determined cut-off point.
the final vote of course. We’re going to restrict voting to just our subscribers.
With two categories – one for organisations (where This is because it will be a lot easier for us to manage
we include distros), and another for software projects, – we’ll be able to easily add the voting interface to the
we now want to create two smaller shortlists that can online subscriptions page for each subscriber, for
be put to a final vote. The reduction to a smaller example, and this limitation also recognises our
number is because we don’t want an unmanageable subscribers for the contributions they’re making. Our
pool of proposals, and to give everyone a better focus plan is to then have three different awards for each
on the final projects that have contention. As this category – one main ‘winner’ and two ‘runners up’
issue goes out, we’ll ask again what organisations, – making six awards in total, which we’ll announce
distros, software, projects and developers people after we’ve hired an accountant and we know how
would like to see supported, and depending on the much we have to give away.
Suggested projects
A quick overview of many of the projects, distros and software proposed
online when we asked which our readers would like to support.
Accessible Computing Foundation Making Gnome Foundation Furthers the goals of the
technology accessible to people suffering from Gnome project by coordinating releases,
various disabilities that normally make conventional sponsoring GUADEC and liaising with both
computing extremely difficult, if not impossible. commercial and non commercial organisations
http://accessiblecomputingfoundation.org interested in Gnome. www.gnome.org
Document Foundation Primarily supports Hacker Public Radio Releases a new community
LibreOffice.org in attempting to give everyone produced podcast Monday – Friday with no
access to office productivity tools free of charge. restrictions on length or content as long as the
www.documentfoundation.org subject is likely to be of interest to “hackers.”
EFF Defending our civil liberties in the digital age, http://hackerpublicradio.org
the Electronic Frontier Foundation champions KDE eV This is the non-profit that represents the
privacy, free expression and innovation. KDE desktop and the KDE community securing
www.eff.org cash, hardware, and other donations to aid
FSF Promoting computer user freedom and the development and promotion. https://ev.kde.org
rights of free software users, the FSF is also the OSI The Open Source Initiative is a global non-profit
custodian of the GNU project and licences. curating and promoting the definition of open
The Free Software
Foundation Europe is a www.fsf.org source and the licences that fit its description.
separate organisation from FSFE Sharing all the same principles as the FSF, the http://opensource.org
the FSF, and doesn’t get FSFE works with the European Commission and Outreach Programme for Women Annual
the credit it deserves. Parliament to create a positive environment for Free internships to help women get involved in Free and
Software and Open Standards. http://fsfe.org Open Source software. http://gnome.org/opw
Practical Action Using technology to challenge
poverty in developing countries by building skills
and knowledge. http://practicalaction.org
Software Freedom Conservancy Promotes,
improves and frequently defends Free and Open
Source software. Projects under its wing include Git,
Inkscape, phpMyAdmin, Samba, SugarLabs, Wine and
many more. https://sfconservancy.org
Young Rewired State An independent global
network, based in the UK, that helps kids ages 18
and under to use open data to make websites, apps
and algorithms for solving real-world challenges.
https://youngrewiredstate.org
38 www.linuxvoice.com
LINUX VOICE AWARDS FEATURE
Distributions
Crunchbang A Debian-based distribution with a
great blend of “speed, style and substance” thanks
to its use of the Openbox window manager
http://crunchbang.org
Debian Announced in 1993 with a first release in
1996, Debian is one of the pillars of the GNU/Linux
distro community thanks to its emphasis on
community and stability http://debian.org
FreedomBox A private server that integrates strong
privacy and encryption to deliver many of the same
features you find from online cloud servers and
services http://freedomboxfoundation.org
Linux Mint One of the most popular distributions
using either Ubuntu or Debian as a back-end and
responsible for the development of the Cinnamon
desktop and the Gnome 2.x fork, Mate.
www.linuxmint.com
Manjaro Based on the newbie-impenetrable Arch
Organisations such as
and using the Xfce desktop, this is a rolling release Blender A 3D sculpting, animation, rendering and
Young Rewired State are
distro with an emphasis on ease of use and games engine that rivals software costing doing a fine job of plugging
installation http://manjaro.org thousands and is quickly becoming an industry the gap in the UK’s IT
Replicant A fully open source version of Google’s standard. www.blender.org curriculum.
Android operating for certain specific mobile Gpodder A popular choice for listeners to our own
devices system that promoted freedom, privacy podcast. It downloads and plays new episodes
and security issues www.replicant.us automatically. http://gpodder.org
Slackware The oldest currently maintained Linux Inkscape A wonderful vector drawing application
distribution, Slackware is still a benchmark for that’s capable of brilliant professional results and
simplicity, security and stability even better output. https://inkscape.org
www.slackware.com MediaGoblin: A decentralised media publishing
Sonar GNU/Linux An accessible distribution that platform trying to compete with YouTube,
bundles assistive technology like a screen reader, SoundCloud and Flickr. http://mediagoblin.org
magnification, on-screen keyboard and a dyslexic- Meld Compare text/code files and visually spot the
friendly font http://sonargnulinux.com differences between them. Great for deciphering
Trisquel GNU/Linux Based on Ubuntu but with a drunken coding sessions. http://meldmerge.org
commitment to remove all proprietary and non-free Nouveau These drivers give Nvidia owners graphics
elements, it’s one of the few distros recognised by acceleration without resorting to closed proprietary
the FSF as containing only free software. drivers. http://nouveau.freedesktop.org/wiki
OpenSSH This secure remote shell is as essential
Software as oxygen to anyone using Linux on a remote
Audacity As used by podcasters the world over. device. www.openssh.com
cross-platform audio waveform editing unrivalled Scribus Desktop publishing that can take your
by functionality or price. words and images and turn them into something as
http://audacity.sourceforge.net magical as a printed publication.
www.scribus.net
VLC Media Player: It plays everything, streams
everything and runs on almost everything. It’s the
media player most of us rely on the most.
www.videolan.org
Xmonad: Tiling window managers make you look
cool. Yes. But they also make you incredibly
productive by keeping distractions and mouse
clicks at bay. http://xmonad.org
ZoneMinder: Home security is normally expensive,
which is why this fantastic open source solution
starting with just a webcam is such a great project.
http://www.zoneminder.com
Now it’s up to you – have a think about which projects
you’d like us to support, and keep an eye on
A few readers reckon Gimp could do with a bit of cash. LinuxVoice.com for he revised shortlist.
www.linuxvoice.com 39
FAQ OPENRISC
OPENRISC
Open source software is all good and well – but how about open source CPUs?
with each generation adding more and you’re willing to pay giant licensing fees
MIKE SAUNDERS more layers of cruft onto the original to Intel or AMD, this probably isn’t an
design. You end up with some CPU option. And even then, you wouldn’t
So, this is free software clone instructions taking just a few clock necessarily get to share your changes
of a certain famous board cycles to execute, whereas others take with the rest of the world.
game, with some kind of pun in the far longer. Now, imagine if the entire design of
title, right? RISC, however, opts for a much your CPU were open. Imagine if the
No, this has nothing to do with smaller range of instructions (and community could work together on
Risk. It’s all about CPU cores here therefore fewer transistors on the improving its performance, features and
– and specifically, RISC (reduced chips), and these instructions are highly power management. Imagine if this
instruction set computing) ones. optimised. Fewer instructions doesn’t could work in tandem with an entirely
OpenRISC is a project that designs mean less capability though; after all, free software stack, so that every byte
completely open processors, which you CPUs just move numbers around in and electron of your computer was free
can study, modify, and have produced in memory and perform calculations on as in speech.
factories. Well, providing you have them. And today, RISC has won: ARM
enough money to do that, of course… chips are built with RISC architecture That sounds like heaven for
and are absolutely everywhere, and Richard Stallman, but how
Hang on a minute! Reduced even though x86 CPUs are still regarded many geeks really want to fiddle
instruction set? Why would I as complex (Complex, rather than with CPU designs?
want that? Give me more, more, Reduced Instruction Set Computing) in Just because it seems like a
more instructions! their architectures, modern ones break black art, or an obscure subject, it
Actually, RISC designs go back a instructions down into smaller doesn’t mean that nobody is interested
long way, and have nothing to do components, in a RISC-like fashion. in it. On the contrary – at the time of
with the overall power of a CPU. They’re writing, the third annual OpenRISC
all about designing the processor so OK, but CPUs are hardware – Conference (ORCONF 2014) was taking
that it has fewer jobs to do – but it can how do you make them open place in Munich, Germany. Forty
do them more quickly and efficiently source? And why would you want to? developers from around the globe
than in other designs. Historically, x86 Yes, hardware doesn’t grow on gathered together to discuss the
CPUs have been complicated beasts, trees (unless you have some current state of OpenRISC, share
fancy wood panelling for your PC case), projects that they’re working on, and
so initially it might seem odd to apply contemplate ideas for the future – see
“RISC designs go back a long FOSS principles to it. But consider
designs: can you take your current PC
page 16 for a full report.
way, and have nothing to do or laptop processor, get a complete So, how are OpenRISC chips
with a CPU’s overall power.” specification for it, change a few parts
and make your own version? Unless
made? How is development
done, and who produces them?
40 www.linuxvoice.com
OPENRISC FAQ
OpenRISC came to life in 1999,
the work of a few computer
science students in Slovenia, and
received a small amount of financial
backing in the early 2000s. Today, the
OpenRISC project is much bigger and
has a few chip designs (known as
“cores”), but currently the focus is on the
OpenRISC 1000, also known as OR1K:
http://opencores.org/or1k. This CPU is
focused on networking and embedded
tasks, with special emphasis placed on
simplicity and low power consumption.
Its design is constructed using the
Verilog hardware description language
– and indeed, you can see the source
code for yourself at https://github.
com/openrisc/mor1kx/tree/master/
rtl/verilog. This code is released under
the GNU Lesser General Public Licence,
so you’re free to base your own chip on
it, as long as you make your designs Experiment with OpenRISC in your browser: try the JavaScript-based emulator (running a
available for everyone else. Linux kernel) at http://s-macke.github.io/jor1k.
For development purposes, the OR1K
design can be implemented in FPGA OpenRISC has been implemented in chip. There’s even some interest in
(field-programmable gate array) many SoC (system on a chip) designs porting FreeBSD to OpenRISC, although
development boards, which means you – that is, chips that include all the we’d wager that NetBSD will get there
can hook up an OpenRISC processor to components needed for a standalone first, given that it already runs on a
various peripherals and create a fully computer. Most notably, Samsung has staggering number of platforms…
working computer. The GNU toolchain used it in various digital TV models,
has been ported so that it can produce while the Allwinner A31, a SoC used in a OK, you’ve sufficiently whetted
OpenRISC binaries, and work is large range of mobile phones, tablets my appetite, and now I want to
underway to get LLVM/Clang to the and smart TVs, has an OpenRISC core make big bucks as a CPU designer.
same state as well. The Linux kernel doing power management work. Where do I start?
itself has been able to run on OpenRISC OpenRISC has even gone into space Well, we can’t guarantee that
since version 3.1, and a few other as part of the TechEdSat project, which you’ll be the Chief CPU Architect
real-time operating systems such as is a satellite designed by students at at Intel after playing around with
eCos have OpenRISC ports as well. San Jose State University – it needed to OpenRISC for a few months, but it’s a
OpenRISC is popular in embedded be cheap, so OpenRISC was a natural great way to dip your toes into the vast
devices, and at ORCONF one developer choice. It could be used in many other wold of processor design. A good place
talked about a project using OpenRISC devices and projects as well, that we to begin is the Getting Started guide at
chips in TV set-top boxes to convert don’t even know about, just as Linux http://kevinmehall.net/openrisc/guide
satellite video data to internet streaming and the BSDs are often chugging away – and note the requirements in
formats. Other embedded chips had inside networking and embedded particular. You should have a solid
been considered, but it was important hardware, without any fanfare. grounding in the workings of a Linux
for the set-top box manufacturer that installation, along with knowledge of
the chips could run the Linux kernel, so Is OpenRISC finished, or is it Verilog and C (the language used to
OpenRISC was chosen. still a work in progress? code the Linux kernel).
Another area in which OpenRISC is With 80,000 lines of Verilog The guide also explains how to run
well known is academia. The Technical behind the design, there’s still or1ksim, an OpenRISC CPU emulator,
University of Munich uses it in research plenty of room for tweaks, performance and how to use the chip on an FPGA
(which is why the conference was held improvements and power savings. A development board. You can pick up
in the city), while many other team of developers is beavering away one of these boards for around £50 to
universities teach courses based on it. on a new CPU pipeline – that is, the £100; see http://opencores.org/or1k/
series of stages used to process FPGA_Development_Boards for a list of
What about the chip in the real instructions. Ideally, it will support boards that work with OpenRISC. But if
world, though – are there any out-of-order execution, along with you really want to dive in at the deep
commercial implementations? dynamic branch prediction. Another end, try the Architecture Manual at
You bet! This isn’t just a play toy topic that came up at the conference http://tinyurl.com/qj6pjfc – just bear in
for hackers and students. was improving the 64-bit version of the mind that it’s 358 pages long!
www.linuxvoice.com 41
INTERVIEW TIM BRAY
< TIM
BRAY />
Graham Morrison meets the co-author of XML, a
fierce privacy advocate, an encryption hacker and
the owner of many hats.
W
atching Tim Bray talk talked about most things to do with
to an audience is a little technology. He’s even making his own
intimidating. He talks security contributions to the amazing
fast and every word counts. And open source Android email application,
he wants action – he wants his K-9. His keynote at OSCON 2014 was
audience to change the world After about threats – threats to our privacy,
founding companies, co-authoring threats to our online freedoms and
the XML specification, working at threats to our data, and “Now is the
Sun Microsystems and then Google time for sensible, reasonable, extreme
(leaving because he famously didn’t paranoia,” as he puts it. Which is
want to leave Canada for Silicon exactly what we wanted to talk about
Valley), Tim has seen, thought and when we met with him.
How do we balance the of technology, it’s purely an issue of
advantages of big data with policy. Now in the US, they have such
healthcare systems and privacy? regulations, the most visible of which is
And how can PGP help with this? called HIPAA, which is widely used and
Tim Bray: Well Larry (Wall, the creator strictly enforced in the healthcare
of the Perl programming language) sector. And, whereas I think almost
certainly puts things into sharp anybody would agree that it’s
perspective. You know, if you’re willing reasonable to have such regulations,
to trust people with your health data the HIPAA itself is not actually very the way people are. So I think that we,
maybe we can save a lot of lives, and good. In particular, it does things like as a profession, have a responsibility to
yet there are a substantial number of mandate the use of specific do the ethical thing by default and not
people who are reasonably paranoid technologies such as passwords when, surprise people with what happens to
about trusting their data to anybody. So quite possibly, better alternatives to the information they share. As you point
if you’re going to do that, you should be passwords would be more secure and out, OpenPGP is a well established, fully
transparent about how you’re going to less onerous are available. debugged cryptography framework
handle the data, how you’d protect it So I would probably appeal to a that is highly implementable and has
and who you’d share it with, and so on. combination of market forces and been implemented lots of times, and
But I don’t think that’s anything like a public regulation to assume the default yet its penetration among the non-geek
complete answer, because the vast action is the right action, is the ethical community is more or less zero
majority of people don’t really have the action, is the action that produces the percent. If we’re not going to make it
education or tools to understand what least surprise on users. If we’ve learnt easy to use by default, then we’re not
the data protection options are, and one thing, no matter how many going to have privacy by default and I
what the consequences of sharing are. information popups you put there think our profession owes the
And we shouldn’t expect them to. It’s a saying what you’re going to do with the community, the people that use our
hard area of expertise and not one that information and what the stuff, privacy by default.
we should expect civilians to have. So I consequences are, a high proportion of
think there’s actually quite a strong role people will say ‘ah, where’s the OK If you look at HTTPS (ignoring
for the public sector in here to establish button, I just wanna get through this’. Heartbleed), even people
regulations, because this is not an issue And whether you like it or not, that’s just without technical knowledge can
42 www.linuxvoice.com
TIM BRAY INTERVIEW
“We owe Mr Snowden a lot of credit
for exposing people to the fact that
their governments are doing things
of questionable legality, morality
and effectiveness.”
understand that a site is encrypted, being brute-force decrypted. It is plenty But it’s taken a couple of years
at least in principle. The certificate good enough. And yes I agree with you to get it into the latest alpha.
sharing is all done transparently and that people are starting to be educated TB: Well, one of the problems with
there’s an authority that deals with about what the little lock means. cryptography is key management, and
the authentication of the certificate. One of the things that I’m how do you find the key for the person
Maybe that’s what we need? disappointed about though is the you want to send a secure message to.
TB: Whenever anyone mentions community of developers that are still Historically, the cypherpunk community
HTTPS, flawed though it is, I have to offering services over HTTP without who invented all this stuff were a little
push back a little bit. Yeah, it’s possible even allowing HTTPS let alone requiring bit guilty of letting the perfect be the
to screw up the installation and HTTPS. What they should all do is go to enemy of the good, and so they set up
deployment and so on, so that it doesn’t their legal department and ask a legal this web of trust mechanism, which
work properly. But when it is deployed opinion, ‘Hey, we’re offering our services never worked – ordinary people won’t
properly, which is not that hard, there is in such a way that anyone sent onto the go to key signing parties. I’m sorry, it’s
not a known instance of HTTPS data company can spy on us – is that legally not going to happen.
OK?’ Well, you know what, it very So I’ve been super interested in this
probably isn’t! thing called keybase.io, which provides
“We, as a profession, have a Even on Android, we don’t
a pretty nice solution to the problem of
acquiring a key with good reasons to
responsibility to do the ethical know of an email client with believe in it. And, what’s great about it is
thing by default.” decent S/MIME PGP support.
TB: So K-9 is getting it.
that you don’t even have to trust
keybase.io. They present everything
www.linuxvoice.com 43
INTERVIEW TIM BRAY
“I don’t care if Apple has signed
it, I want to download an app
that has previously been
audited and found to be safe.”
that you need to know in proofs that huge proportion of internet traffic. We experience more private and safe for
you can independently verify if you did not know they were tapping into all the people that are going to come
want to. I thought the difficulty of Google’s data centre. after us.
actually discovering and acquiring keys
might be the single largest remaining And you worked at Google for a But even with all the data
logjam, or one of them anyhow, in while… anonymised, there’s no one
making quality cryptography available. TB: Yeah, and I tell you, the people at accepting anyone’s word that it’s
Now I think we’re ready to make that Google were livid when that one came anonymised, and even when it is
one go away, and so I’m optimistic. to the surface. So I think we owe Mr anonymised, you only need
Snowden a lot of credit for exposing the something like three trig points to
GnuPG for email clients can larger population to the fact that their find people. There’s just so much
work completely transparently governments are doing things that are data out there. It seems to us like
as far as key exchange and key of questionable legality, morality and the cat’s already out the bag.
discovery go. You don’t even have to effectiveness. TB: Well sure, you can take that
know anything about the keys. attitude. And also you can say that
TB: And particularly in the case of In the UK – thanks to the anyone who carries a mobile phone is
keybase, you just go ‘I’m looking for a European Court of Justice – it revealing their location at all times. But I
key for you’, and it says ‘Oh, here’s a key, is illegal to harvest data from ISPs think the notion that the cat’s out the
which is also controlled by the person on a large scale and that’s why bag and we should all roll over and give
who controls your Twitter account and they’re rushing through these very up is just barshit. I think that every time
your GitHub account’. OK, that’s good quick surveillance laws to make it we increase the proportion of the traffic
evidence, I’ll believe that that key is a ‘not’ illegal. that is privacy-enabled, we are doing a
good one to encrypt my message with. TB: Right, the DRIP [Data Retention and public service. We are driving up the
Investigatory Powers] law. We’re having cost to those who have been abusing
When do you think this became a similar problem in Canada, although the existing transparency, and I think
such a big issue? Has it always one of our courts found that it is illegal that’s something we should do. We
been an issue, or has it become for ISPs to provide usage data without have no excuse for not doing it.
more an issue as the internet has a warrant, which is a change in the
become so much a part of our lives? landscape. But we’re in the minority. The
TB: I would offer a lot of credit to Ed new generation are used to
Snowden, who started this Do you think it’s too late? Facebook and everything about their
conversation. I think a lot of people, Do you think the cat’s out of lives being online.
security professionals and people close the bag? TB: From what I hear, the younger
to metal, kind of knew what was going TB: Oh no, not in the slightest. We’re generation is increasingly less
on. Knew that, you know, government still in the first generation of people who Facebook-centric and one of the
agencies were in fact scooping up a live on the internet. We can make the reasons for that is they don’t like that
44 www.linuxvoice.com
TIM BRAY INTERVIEW
creepy feeling that their information is equipped to make it, so why don’t you happening for reasons that are actually
leaking. Just because an opinion one just do the safe thing and make good. Native mobile apps offer more
holds is in the minority, doesn’t mean everything private. And that’s an responsiveness and a lot of UX options
we should give up and stop pursuing it. unanswerable argument now that that are not available in browser apps.
And, like I said earlier, I don’t think we HTTPS is very low cost and low They also have an important advantage
should expect the general population to difficulty to deploy. I’m quite optimistic that we’re not giving enough credit to,
have educated opinions about internet actually. I’m not arguing in favour of which is that they also have a superior
safety any more than they have absolute privacy; there can never be developer experience. However, there
educated opinions about emission such a thing. All we can ever do is move are two important advantages of the
control systems in automobiles or air the needle and increase the proportion browser-centric world that we’re losing.
traffic control regulations, and that kind of things that are privacy enabled, and I One of course is the speed of update. If
of thing. It’s our responsibility as think we’re doing that. you have a bug that you need to fix fast,
professionals to ascertain what the I notice that there are excellent in the case of Android you’re looking at
most beneficial behaviour is and build OpenPGP libraries available now for a latency of hours and in the case of
things in that way. Ruby and Python and JavaScript and Apple you’re looking at a totally
Node. There are not for Java itself or for unpredictable latency of potentially
“I’m not arguing in favour of .Net, which is a problem that we need
to address. I know that people are
weeks, whereas if you’re web-centric
you can fix an applet in minutes. And
absolute privacy; there can working hard over at Google and some that’s huge. Secondly, the issue you
never be such a thing.” other places about trying to do crypto in
the browser. Which is, if you can do it, a
raised is important to me. I think the
internet is better when anyone can
super interesting enabler of a bunch of deploy anything on it without asking for
It’s one thing to say it, but interesting things, but there’s a severe permission. And anyone can go and get
we’ve known about this for a question of trust. When can you trust it. And I do not like the app store as
long time and it hasn’t happened. an app that you download over the air? intermediaries through which you go to
TB: I’m disturbed by your counsels of Those problems are not insuperable. find anything. I’m less offended by the
dispair. The proportion of things being Google app store than by Apple’s
transmitted over HTTPS is Do you think we can counteract because of its exclisivity – when Apple
monotonically increasing. And we still the new app-centric frontier by says we’re not going to sell something,
encounter people saying ‘oh, my stuff is using stuff like Firefox OS? they’re not saying they’re not going to
shareware, it doesn’t need to be TB: It is clearly the case that the sell it, they’re saying you can’t have it. If
HTTPS’. And to that I say, ‘well, yeah, browser is becoming less central as Google doesn’t like something, well you
but the decision as to whether part of the software delivery ecosystem can still get it off the project’s website,
something needs to be private is because a very high proportion of right? How much impact is something
complicated and very context things are migrating into native mobile like Firefox OS gonna have? Well, I hate
dependent, and most people aren’t apps. And to some extent that’s to say it, but that probably depends on
price performance of the hardware it’s
running on.
We lament the loss of what the
internet had at the beginning
of its life.
TB: Think about it this way, the volume
of traffic on the internet is unimaginably
vast. So whether you are an over
enthusiastic government agency or
whether you are a hacker trying to steal
credit card numbers, every time we can
impose a non-zero cost on surveillance,
the volume is so high that there will be
entire class of surveillance or an entire
class of crime, that it becomes
uneconomic. And, given that, why
would we not do it? Every time you
increase the proportion of traffic with
HTTPS up by 5%, you drive a certain
class of undesirable behaviours into
Tim’s a fan of the way apps make things
uneconomic territory. You don’t have to
easier for developers – but not of the
disadvantages they present to users. win to win, you just have to make things
better to improve the environment.
www.linuxvoice.com 45
BUY MUGS AND T-SHIRTS!
shop.linuxvoice.com
INTRO REVIEWS
REVIEWS
The latest software and hardware for your Linux box, reviewed
and rated by the most experienced writers in the business
On test this issue...
48 50
Andrew Gregory
So this is what bandwidth shaping looks like.
Thanks BT, thanks a lot.
O
ne of he few good things to
have come out of the recent/ Ubuntu 14.10 FRITZ!box 7490
current Gamergate campaign Ben Everard is bemused by the newbie Paranoid BT customer Graham Morrison
of harassment is that Kathy Sierra has distro par excellence offering upgraded switches router to a device that won’t
returned to the internet, this time to developer tools in its latest offering. send all his data to GCHQ.
introduce (to me, at least) the concept
of the Kool-Aid point. This imaginary
construct is that point at which 52 53
something achieves a degree of
popularity; trolls are then given licence
to attack the idea/person/thing merely
because it’s popular. The merits of the
thing in question go out the window; all
that matters is that if it’s popular, it is by
definition inferior in some way.
Ubuntu is popular. It’s still the Linux
distro with the biggest chance of
getting through to the masses, and FreeBSD 5.6 Google cardboard
there’s a predictable queue of critics The grass may not always be greener, but After a greasy pizza, Ben Everard sticks
lining up to slate it for any number of Mike Saunders does like to look at an the box on his face and pretends he’s in
reasons, both real and imagined. alternative OS to Linux now and then. The Lawnmower Man. Thanks Google!
Likewise Google. Google is an
advertising company. Its key revenue
driver is advertising, built off the back of BOOKS AND GROUP TEST
the best search engine in town. It
One of the best things about Linux from an ethical
doesn’t need to make 3D cheaper for
point of view is that it runs on old hardware. Linux
everyone, or provide free translation and free software has the potential to keep tonnes of
services, or do any of the other things it rare metals out of the landfill site (and save you a
does that make our lives easier. By all few quid in the process), and it’s all thanks to
means knock them for the creepy lightweight Linux distributions such as those tested
on page 56. If you have a machine gathering dust,
privacy invasions, but Canonical and
install one of these and marvel at the resurrection.
Google aren’t privatised state And over in book reviews there’s a filmic interloper in
monopolies like BT – we can’t knock the shape of patriot/traitor Edward Snowden biopic
them just for being successful. Citizen Four. Seek it out; it’s rather good.
andrew@linuxvoice.com
www.linuxvoice.com 47
REVIEWS UBUNTU 14.10
Ubuntu Utopic Unicorn (aka 14.10)
Long-term Ubuntu user Ben Everard discovers whether Deckard was a replicant.
T
he biggest news about the Utopic Unicorn
DATA isn’t what’s included in it, but what isn’t. Mir (a
Web
display server) and Systemd (an init system
www.ubuntu.com – see page 86 for much more) are both coming to
Developer Ubuntu, and they’ll both have a profound effect on
Canonical how it works. However, they’re both going to arrive in
Price the release after this (15.04, aka Vivid Vervet). Without
Free under various
licences
these, Utopic Unicorn is a boring release in many
ways. Without Mir, there’s no Unity 8, so the desktop
environment hasn’t changed significantly from 14.04
(though it does work better on High DPI displays)
In fact, as far as desktop users are concerned,
the biggest changes are the inclusion of the latest
packages. Unity will still include online results in searches in the
Linux 3.16 The kernel upgrade brings some Dash – a move that angers many privacy campaigners.
performance improvements.
Firefox 33 Brings some significant performance
improvements to web browsing. a big problem, but if both Systemd and Mir arrive
LibreOffice 4.3 This has improved DOCX support on schedule, they’ll both be coming in 15.04. This
Other than this, the updated versions of Libnss means that by choosing to install 14.10, you are
means that Netflix will now work out of the box with effectively choosing to switch to Systemd and Mir in
Chrome. Unlike the previous release (Trusty Tahir a few months’ time. Even if you like the idea of these
aka 14.04), Utopic is not an LTS (Long Term Support) technologies, the first version of a distro containing
release. This them is likely to have a few problems. Unless you’re
“Anyone wanting to develop on means that it will
only be supported
prepared to endure these problems, a more prudent
approach would be to install 14.04, which will be
cloud services may find that for nine months. supported until April 2019.
Utopic is the best distro for them.” Since releases
come out every Developers developers developers!
six months, this There is, really, only one significant release from
means that users either have to upgrade every time, Canonical in 14.10, and that’s the Ubuntu Developer
use an unsupported system or switch to another Tools Centre (UDTC). The idea behind this tool is that it
distro altogether. Usually, upgrading each time isn’t will enable developers to quickly set up common
development environments. The first environment is
for Android development including the various tools
Flavours
from Google. It’s not hard to set these up, but there are
Of course, Ubuntu isn’t just about the Plasma 5 and experience the future. a few bits that need to be downloaded, and
default version with the Unity desktop: there Xubuntu Not much has changed in Xfce, dependencies installed. UDTC acts like a sort of
are seven official flavours of Ubuntu with but Xubuntu users can upgrade to take package manager that enables you download
different desktop environments. Canonical advantage of the latest packages.
hasn’t released any information about how Lubuntu LXDE only gets some bugfixes
everything and set it up in one go.
popular they are, so we’ve ordered them by this version, as most of the development is This is useful – it slightly reduces the amount of
the number of people seeding the ISO on going into LXQt. This is another distro with work that a small minority of people will have to do
BitTorrent. a big change coming up. after installing Ubuntu – but it’s not really a killer
Ubuntu Gnome The newest official flavour Ubuntu Kylin The Chinese version of feature. After all, not many people will even need it.
of Ubuntu has proved to be very popular, Ubuntu comes with a more tweaks than
and shows that many Ubuntu users would just the language. For example, WPS Office
We can certainly see it becoming more useful over
like to stick with the distro’s roots. ships as the office suite because it’s more time. For example, if it becomes easy to define the
Unfortunately, the release schedules of popular than LibreOffice in China. environments that get installed, you could create
Ubuntu and Gnome just fell out of sync, so Ubuntu Studio As well as the usual raft of custom ones for particular projects so the whole team
14.10 ships with Gnome 3.12 instead of changes, the new kernel brings ALSA can easily stay updated, and new members could
the slightly newer 3.14. support for firewire devices.
Kubuntu KDE is also in for a big upgrade Mythbuntu This hasn’t released a 14.10
instantly get everything they need. However UDTC is
soon. By default, Kubuntu still ships with version as there weren’t enough changes still some way off this ideal.
Plasma 4, but intrepid users can switch to to make the non-LTS release worthwhile. If you’re using Ubuntu 14.04 and like the sound
of the UDTC, you don’t need to upgrade your whole
48 www.linuxvoice.com
UBUNTU 14.10 REVIEWS
Desktop next
As we’ve mentioned, 14.10 is, well, a bit of a boring release
for the desktop. But this doesn’t leave the thrill-seeking
distrohopper without an exciting version of Ubuntu. As we’ve
mentioned, there are a lot of changes stacking up for the next
version (15.04, aka Vivid Vervet), and there are already images
of this distro that you can install.
Given that this is still months away from release, you
should expect quite a lot to be broken, and even more to
break with upgrades, so it probably isn’t suitable for a main
computer yet even if you do know what you’re doing. However,
if you want to see what’s going to happen next release, fire
it up and have a look. In some versions of Virtualbox, it’s not
starting correctly. If you end up with a screen of colourful
characters instead of a desktop, press right-Ctrl+F1,then
right-Ctrl+F7.
distro; you can get it by adding the PPA:
sudo add-apt-repository ppa:didrocks/ubuntu-developer-tools-
center
After years of seeing Ubuntu as a newbie-friendly The Dash is Unity’s most powerful feature. It’s a central place that enables you to search
distro, it seems strange to be talking of Utopic Unicorn a wide variety of sources. Here, it’s searching both installed, and available applications.
as a distro for more technical users, but it seems to
be the more experienced Linux users who will benefit Openstack
most from this release. As well as UDTC, there are a While many people often think of Ubuntu as a
number of rapidly developing new technologies that desktop distro, it’s also one of the most popular
have been updated: Linuxes for running cloud services, and it’s Ubuntu’s
Containers tight integration with technologies like these that
Juju have earned it this spot. Of course, not many
sysadmins are going to be rushing to switch their
servers to a distro that’ll only be supported for nine
months. However, anyone looking to develop on
these technologies may find that Utopic is the best
distribution for them right now even if they release on
a different system later on. This release of Ubuntu is
also a great place for anyone looking to learn these
tools (and learning these tools is a great idea if you
plan on being in the sysadmin or cloud computing
world in five years time).
Keep calm and carry on
Overall, Utopic isn’t an exciting release for most
desktop users. In fact, we’d go so far as to
recommend most desktop users stick with Trusty
Tahr (the most recent LTS version) for now. The
exception to this is anyone interested in the developer
tools, whether this is the UDTC or the cloud computing
software. For these people, Ubuntu is becoming a very
attractive option. That doesn’t mean it’s time to write
Ubuntu off as a boring distro. There are big changes
afoot. It’s too soon to say whether they’ll be for better
or worse, but this will probably be the last boring
Ubuntu release for quite some time.
LINUX VOICE VERDICT
An unexciting release with a short
support period… but be prepared for
KDE users with a long memory will be wary of a new big changes to come.
major version, but Plasma 5 on Kubuntu looks good, even
if it’s not the default version yet.
www.linuxvoice.com 49
REVIEWS FRITZ!BOX 7490
FRITZ!Box 7490
Graham Morrison’s distrust of his ISP’s standard router has led him to a German
alternative with a rather self-deprecating name.
T
his is a beast of a router. It’s also quite occasional unrecoverable errors that the HomeHub
DATA expensive and nowhere near as open as a didn’t, but equally, it could go for weeks without a
Web
device running the OpenWrt distro for single problem. A firmware update that came late
http://en.avm.de embedded devices. But it’s worth considering for a October (6.20) seemed to improve stability again, and
Manufacturer couple of reasons. added more feedback about the connection.
AVM Computersysteme Most importantly, it can be used to replace the
Price devices supplied by the UK’s biggest fibre provider, BT Such numbers, wow!
£240
Infinity. BT provides a proprietary and vendor specific The feedback you get from the FRITZ!Box is fantastic.
unit it calls the ‘HomeHub 5’ to its customers – a There are more geeky statistics on the quality of your
wireless access point and VDSL modem combined. connection than on any other router we’ve seen. An
They’re powerful, stable and more than adequate, online monitor shows both a downstream and an
SPECIFICATIONS
especially in the fifth revision now being sent out. upstream chart split by category of the data flowing
VDSL or ADSL But BT also has a dubious record with its customer’s into and out of your network. This is very useful if you
IP or analog phones privacy, including reports of ‘remote diagnostic tests’, want to immediately see how much bandwidth Netflix
4 x gigabit Ethernet
its collusion with a commercial service that scanned is consuming, as well as how much headroom you’ve
WAN on LAN 1
Wireless AC (1300 your network packets to deliver tailored advertising, got for playing Borderlands 2 with your friends. There
Mbit/s) and rumours of BT allowing a government back- are charts showing the signal-to-noise ratio across the
Wireless N (450 Mbit/s) door, NSA-style, into its hardware. The second and broadband spectrum, a page of statistics, and a page
2 x USB less tinfoil-hat reason is that the FRITZ!Box 7490 is that allows you to adjust the signal-to-noise ratio,
Handles 6 DECT
much more powerful, giving you far greater control impulse noise protection and radio frequency
handsets
ISDN S bus and feedback over your connection and replacing a interference to create a faster or more stable
Average power: 9.3W multitude of devices within your home. connection. These had no effect with VDSL, but they
The most important feature for a device like this were able to make a troubled ADSL connection more
is the speed and stability if its internet connection. stable for us.
Every other feature hangs off its success, and we’d We also like the simplicity of Access Profiles. These
even forgo our privacy issues and stick with the are a basic whitelist/blacklist system that can be
HomeHub if it made the difference between watching grouped into profiles and applied to specific devices,
Taylor Swift’s videos in 1080p/60Hz, 24 hours a day, or guest networks, on your network. You can filter
or ordinary standard definition at tea time. We’ve on applications and by websites and block them
tested the unit with both a slower ADSL connection completely or for a specific day and time. These lists
and a fibre-based VDSL connection, and we had provide a no-fuss way of locking down a child’s device
good results over weeks of use. VDSL suffered from or cutting off their connections at a specific time. The
firewall is equally well specified, allowing services
and ports of your own creation through to specific
devices, and there’s a great overview of what devices
are connected, what they’re doing across the network,
and at what speed they’re connected. Other network
features include access to the NAS and a portal that
can make your router configurable from the internet.
The NAS feels a little simplistic, and we don’t think it’s
going to challenge QNAP and Synolgoy devices, but
it offers most features you’d expect, including access
control and UPnP for media streaming. Just plug in a
USB storage device and go.
Cable metropolis
The unit has four Gigabit Ethernet ports, and the 4th
can be used to access the ‘Guest’ profile to limit
access to any services running on your LAN. Wireless
is via both a 2.4GHz frequency network and a 5GHz
network. Without scientific testing, we’d say coverage
It looks like something out of Elite Dangerous, and the FRITZ!Box 7490 connected to our wasn’t as good as the HomeHub, but we had better
VDSL at the native speed for our line – 80 kbit/s download and 20 kbit/s upload. throughput performance, especially after restricting
50 www.linuxvoice.com
FRITZ!BOX 7490 REVIEWS
Hack your FRITZ!box
There’s a surprising amount you can do with the FRITZ!box if
you’re willing to hack around a little. Telnet can be enabled,
for instance, by pressing ‘#’ on a connected phone, and
dialling 96*7*. You’ll even see a message to tell you it’s
enabled (switch the 7 to an 8 to disable it). You can now
connect to your router from the command line by typing telnet
ip_address, and entering your web admin password. You’ll
now find yourself in a fairly recognisable Linux command line
environment. You can ls or type top and take a look around
the filesystem. wget is also available and there are ways of
installing user-compiled packages like ‘DropBear’, but we
wouldn’t suggest doing this.
Instead, we’d recommend taking a look at the Freetz. This
is a collection of open source modifications that can be made
to your router’s default firmware, turning it into a much more If the default firmware doesn’t give you enough
flexible and hackable device (and likely voiding the warranty control, you can access the OS with Telnet or install
at the same time). You need to create a virtual machine with an open source update called Freetz.
a specific build environment and then pull the latest files from
a GitHub account before building it all from a basic menu hardware, and the ability to make your own firmware changes,
system. Nearly all the important and relevant information it’s worth the effort. We found it particularly useful to add
is in German, making the task that much harder if you don’t wider VPN functionality, including OpenVPN, as well as easily
speak the language. But if you want greater control over your adding SSH and other applications.
5GHz to our faster devices. You can also turn the to your configuration, turning any connected phone
wireless off to a schedule and create a separate into an IP phone. We tested this with a free account
network for guests, which is a feature we really like. from www.voiptalk.org and it also worked perfectly.
There are several supporting apps you can install You can block, divert and forward calls, depending
on your Android phone, and one is called ‘WLAN’. This on simple rules, and manage which network is used
gives exceptional diagnostic information about the for dialling. If you want to trust the internet portal
strength and frequencies of any networks overlapping forwarding, you can even see your missed calls and
yours, including the field strength over time and the messages from outside your network, making the box
ability to beep when it gets out of range. We found a good contender for a small business.
this an excellent tool for fine-tuning the network and The best thing about the FRITZ!box is the huge
making up for the weaker performance on the router. amount of
As mentioned earlier, you can also pair the router
with your DECT-compatible phones and connect your
information
and control it
“The best thing about the FRITZ!box
land line to your router to accept calls. You need to provides, and is the huge amount of information
make sure you get the UK version for the UK cable, as
it’s a weird mix of broadband and phone that might
it’s a refreshing
change from
and control it provides.”
not be easily found otherwise. You can enable both the limited data
a fax and an answer machine on the FRITZ!box, spat out by the routers shipped with most ISPs. For
and best of all, another app on your Android device example, there’s plenty of control over power usage,
will turn your mobile into yet another phone. When allowing you to reduce the speed of the network, or
connected to the WLAN, the app will allow you to the wireless, or the DECT phones to save electricity.
answer and make landline calls, listen to messages, There are still trust issues with proprietary firmware,
make internal calls and see any missed messages, of course, and we missed specific ‘Quality of Service’
as can any other connected phone. This system controls, but we feel a lot less paranoid while running
works brilliantly, and we forgot we were answering a the 7490 in place of our normal HomeHub 5.
landline call from our mobile thanks to the app being This is an expensive router, but if you’re looking to
so transparent. You can also add internet telephony replace an old DECT phone system, a NAS server and
media player, in a box that can handle FTTC and ADSL
connection (including Annex M), or you run a small
business, it pays for itself.
LINUX VOICE VERDICT
Expensive, but more Linux-friendly than
your ISP’s default, and it can replace
There are two USB 3 ports for printers and storage media, more than one device.
as well as analogue phone ports for telephones,
answering machines and a fax.
www.linuxvoice.com 51
REVIEWS OPERATING SYSTEM
OpenBSD 5.6
Bang on schedule, another release of OpenBSD is here.
Mike Saunders pits it against the current crop of Linux distros.
O
penBSD has a lot in common with Linux. It’s
DATA Unix-like (actually a descendant of BSD Unix),
Web
it’s open source, it’s reliable, it’s secure, and it
www.openbsd.org runs most of the software you’re familiar with: Gnome,
Developer KDE, Firefox, Apache, MySQL and so forth. But it’s a
The OpenBSD Project much smaller project, with a comparatively tiny
Licence development team, so is it fair to compare it with
BSD, ISC, GPL and more
Linux? We think so, given that it does a very similar job
to Linux, and many OpenBSD advocates recommend
making the switch. But we understand that it doesn’t
try to be an all-singing, all-dancing desktop OS like
many of the big-name Linux distros.
OpenBSD 5.6 is available for several platforms,
including x86, x86-64, PPC, Sparc and various ARM OpenBSD’s manual pages are fantastic, and document
boards. An absolute minimum installation requires virtually every aspect of the OS.
just 32MB of RAM and 200MB of hard drive space, so
it’s great for turning an old box into a router, firewall or The biggest change in this release is the inclusion
small server – tasks at which OpenBSD excels. of LibreSSL, the OpenBSD project’s fork of the hack-
filled OpenSSL codebase. Some pundits criticised
Out with the old, in with the new OpenBSD for forking and not simply submitting
As with previous releases, the installer in 5.6 is plain patches, but as we’ve seen with OpenSSH (another
text and to the point, and it’s hard to get stuck OpenBSD project that’s now used everywhere), the
because the documentation is so good. OpenBSD developers know what they’re doing. On laptops, the
prides itself on having clear and correct Intel and Radeon DRM drivers now have improved
documentation, and although its developers and suspend and resume support, while Sendmail has
users are often accused of chanting “RTFM” (read the been dropped from the base system in favour of
fine manual) all too often, that’s understandable. The OpenSMTPD. Other cleanups include the removal of
installation guide is very thorough, and the “afterboot” Kerberos and the old Apache-based web server, with
manual page provides an excellent introduction to the latter being replaced by a small daemon based
OpenBSD is pretty bare
out of the box, but point configuring your new OpenBSD setup. Very little is on relayd. Old-school FTP and tape installations have
$PKG_PATH at a mirror of installed by default, but there’s a large range of binary faced the chop as well in this release.
packages and run pkg_add packages for desktop, office, server and development Now, OpenBSD prides itself on being extremely
xfce to get this. jobs just a few pkg_add commands away. secure, beyond Linux and the other BSDs. We often
see newly discovered exploits that wreak havoc on
other OSes, but are more contained or simply don’t
work on OpenBSD. This is great, but keeping the
system up to date is so much more work. OpenBSD
doesn’t have official binary updates – so when a bug
or hole is discovered, you have to manually patch and
recompile the kernel and/or userland yourself. There
are some third-party providers of binary updates,
but when you compare the work involved to apt-get
update && apt-get upgrade, it’s a bit off-putting. We
understand that the OpenBSD team is small and
very busy, so we won’t knock them. It’s just worth
considering before making the switch.
LINUX VOICE VERDICT
Plenty of old cruft removed, plus
some minor updates. We still hope
for binary updates one day though.
52 www.linuxvoice.com
GOOGLE CARDBOARD REVIEWS
Google Cardboard
Ben Everard builds a virtual reality headset from an old pizza box.
Forget jetpacks and hoverboards – this is the future.
T
he idea behind Google Cardboard is simple:
take a mobile phone, place it close to your
eyes and use one half of the screen to display
an image to one eye, and another half of the screen to
display an image to the other eye. This creates a
stereoscopic 3D image that has half the horizontal
resolution of the phone.
Google Cardboard does this with a piece of folded
cardboard that fits onto your face and includes a
pair of plastic lenses to help your eyes focus on the
screen. There’s also an NFC tag so your phone can tell
it’s in the device and a pair of magnets to provide input
to the device.
You can buy kits with the cardboard pre-cut (from
Amazon, DX.com or others), or you can just get the
lenses and NFC tag (and magnets as well if your
phone is compatible), then download the design files
Anything that can output
and make it from any pieces of cardboard you have is only really suitable for simple applications and not
two images side by
lying about. serious 3D work. This is a shame, and we hope that a side can be used with
The biggest problem with Cardboard is how solution is found. Cardboard. This is the
incompatible it is with many devices. More or less any rollercoaster from http://g.
phone should be able to display 3D images and video. What would MacGyver do? co/chromevr
The best source of these is probably YouTube (search The magnetic switch is probably the least reliable part
for SBS 3D to find glass-compatible videos). Phones of Cardboard. This should work with the Nexus 5, with
with a hardware gyroscope can also do head tracking, other phones hit-and-miss at best. Without the
enabling you to look around the 3D world. magnetic switch, the method of getting input into the DATA
In fact, the gyroscope is probably the biggest phone is to poke your finger through the nose hole
Web
problem with Cardboard at the moment. Not only and tap the screen. This is inelegant, but it works. https://cardboard.
do many phones (even some listed as ‘partially- Apparently, you can use a strip of copper tape to withgoogle.com
compatible’ on Google’s website) not have one, but conduct a touch from outside the device to the Developer
those that do often have calibration problems that screen, but we’ve been unable to test this. Google
Price
leave the 3D world slowly spinning (a problem known Cardboard feels like (and it is) a hacky prototype
No official price. Various
as gyro drift). It might be possible to correct (or at stage. It’s far from a consumer-ready device, and unofficial options from
least minimise) this problem in software in the future, there’s not a lot of software available for it yet. about £5.
or this might prove too complex. For now, at least, However, given the price it’s selling at, we think that
this problem means that head tracking in Cardboard this is acceptable (gyro-drift aside). In fact, playing
with Cardboard is ridiculously good fun partially
because it feels so hacky. It literally is a virtual reality
headset that you can build yourself, and that alone
is enough to get us excited. There’s just something
about being able to use a device you’ve built to look
around in a 3D world that restores our child-like
wonder in computing far more than any closed off
device you can pick up off a shop’s shelf. We’re giving
Cardboard a maximum score because its such a joy
to use, not because it works perfectly.
LINUX VOICE VERDICT
The most fun you can have with
an old pizza box. Just don’t expect
The standard Cardboard (shown here) should fit most everything to work perfectly.
phones, but there’s an unofficial large version that claims
to fit phones up to 7 inches in size.
www.linuxvoice.com 53
REVIEWS FILMS
Citizen Four FILM
Ben Everard didn’t use Tor to book his cinema tickets
and has now been flagged as a troublemaker.
I
n mid-2013, a trio of journalists boarded directly into the hotel suite in Hong Kong for
a plane to Hong Kong to meet a the meetings. We see Ed’s reactions as the
mysterious person who had recently story blows up, but it’s told subtly. Viewers
delivered a small cache of classified have to watch closely to see how his body
documents from the NSA. The source betrays his stoic words.
promised to reveal more once they met. The footage of Snowden is interspersed
Those three people were Glenn Greenwald with speakers on privacy and encryption
(a lawyer turned blogger and columnist), including William Binney (the former NSA
Ewan MacAskill (a reporter for the Guardian) leaker), Jacob Appelbaum (Tor developer,
and Laura Poitras (a documentary film journalist and privacy campaigner), and
maker). The person they met turned out to Ladar Levison (former owner of Lavabit).
be Edward Snowden and the rest, as they Together, these help give an idea of the
say, is history. impact that total surveillance can have on
Or is it? Many words have been spoken a society.
about Ed (as he likes to be known), but little
has been said. Up until now, the three people The human element
who met him in Hong Kong have, for the There’s little about the details of the leak –
most part, kept their reporting to the leaks, it’s been well covered elsewhere and film “My name is Edward Snowden. I go by Ed”.
not the leaker. Although the mainstream isn’t the right medium to explore them.
media has dug through his past, he hasn’t Instead, the film adds a human element to something is sent encrypted, we see gpg
yet told his story, and while the history books the saga. This has been much missed up spit our seemingly random alpha-numeric
are full of details of the data leaked, there are until now (with, perhaps, the exception of the characters (no, we don’t know if these are
still some gaps in the public knowledge of excellent book The Snowden Files by Luke actually the encrypted files). When it shows
the leak itself. Harding, but that book focused on the the command line, what else would you
Citizen Four doesn’t completely change impact on the media establishments and expect, but Tails’:
that – it’s ultimately a film about the actions journalists working at them, not the four amnesia@amnesia
of the American surveillance state, and people holed up in a crowded Hong Kong These are of course small details, but the
Poitras’s experience with that, rather than a hotel room). accuracy there gives us confidence in the
biography of Edward Snowden – but it does The geek viewer will appreciate that accuracy of the film as a whole. Another
offer a few glimpses round the side of the the technical scenes aren’t faked (as so nice touch was the inclusion of Tor, Tails
media firestorm. Poitras takes the viewer often seems to happen in films). When and Debian Gnu/Linux in the film’s credits.
Eagle-eyed viewers will also learn that Ed’s
reading material of choice in Hong Kong
was written by Cory Doctorow.
The film concludes with a confirmation of
the much-rumoured new leaker from within
the American surveillance establishment.
Few details are given, but much is hinted
at. Linux Voice attended the UK premier
which included a Q&A session with Potrias
where someone asked the director for any
new details. Her refusal to answer gave us
reason to suspect that we could be in for
We appreciated the accuracy of some of the technical details, like including a real command line some more exciting (and worrying) news
rather than the fake ones you normally see whenever Hollywood touches on tech. stories in the future.
“Citizen Four is ultimately a film about the actions LINUX VOICE VERDICT
of the American surveillance state rather than a
Footage from inside the hotel room as
Edward Snowden leaked the NSA’s secrets.
biography of Edward Snowden.”
Need we say more?
54 www.linuxvoice.com
REVIEWS BOOKS
Jaquard’s Web: How a hand loom led to ALSO RELEASED…
the birth of the information age
19th century programmable clothing? Ben Everard is intrigued.
T
here was one interface that
remained virtually unchanged
from before Charles Babbage
designed the Analytical Engine to well into
the 1960’s: punched cards. Curiosity has spent
These were first used by innovative over a Martian year
weaver Joseph-Marie Jaquard to improve (687 Earth days) on
Don’t be fooled its new home .
the speed at which silk could be woven
by the cover
into designs. These looms inspired Mars Rover Curiosity
– surprisingly
Babbage in his ultimately futile quest little of this If you’ve built Ben’s ice cream carton robot
to build a mechanical computer, they book is actually from issue 4, and you’re looking for a new
were instrumental in the pre-computer about weaving challenge, this book is going to provide the
perfect insight. Written by Curiosity’s Chief
calculation machines, and they were clothes.
Engineer and endorsed by Buzz Aldrin, it’s got
considered essential components in to be a must read.
almost all early computers. LINUX VOICE VERDICT
Essinger follows this narrative and Author James Essinger
encourages us to follow the links from Publisher OUP Oxford
looms that weave silk to machines ISBN 978-0192805782
Price £9
that weave information. Overall, it’s an
A slightly unusual angle that forces us to
enjoyable read, and even people with quite think about the data rather than the machine.
a bit of knowledge of computing history
will probably learn something from it. The 2nd
edition dumps
Bukkit in
Metasploit: The Penetration
favour of the
CanaryMod
library
Tester’s Guide Learn to program with Minecraft
Ben Everard learns how to exploit computers using PDF files. Kids love Minecraft. It’s amazing. This second
edition of a proven child-friendly title promises
A
that no prior coding experience is necessary,
nyone interested in computer and that your firstborn will soon be creating
security will have come across flaming cows, flying creepers, teleportation,
Metasploit. It’s a framework that and interactivity.
can help with just about every aspect
of penetration testing from information
gathering to post exploit work. However, to
HD Moore – the
do all this, it has become quite a complex
founder of the
beast. Learning to use Metasploit is more
Metasploit
like learning to use a new programming project –
language than learning to use most other endorses this
applications. book in the SVG is a long
Metasploit: The Penetration Tester’s Guide forward. way from the
is well titled: it’s a guide to Metasploit for turtle graphics
penetration testers. It isn’t written for we cut our
LINUX VOICE VERDICT teeth on.
people with no pen testing experience,
Author David Kennedy, Jim O’Gorman, Devon
but it does start at quite a basic level and Kearns and Mati Aharoni SVG Essentials
while it assumes the reader understands Publisher No Starch Press SVG is about more than being a scalable image
ISBN 978-1593272883
basic principals about how computers format. It can be used for animations, charts,
Price £32.50
and networks work, it doesn’t assume any web design and includes transforms and
A great introduction to the software, but gradient, all from its text-based XML. This is a
prior experience with Metasploit. It’s a very you’ll need some knowledge of penetration book aimed at designers that doesn’t ignore
practical book, and a large proportion is testing to get the most out of it.
the complex stuff, making your output visually
taken up with code examples that are well and functionally more powerful.
annotated and explained.
www.linuxvoice.com 55
GROUP TEST LIGHTWEIGHT DISTROS
LIGHTWEIGHT
DISTROS
GROUP TEST
Mayank Sharma is on the lookout for distros tailor made to infuse
life into his ageing computers.
On Test Lightweight distros
T
here has always been a some text editing, and watch some
Linux Lite demand for lightweight videos. These users don’t need
URL www.linuxliteos.com alternatives both for the latest multi-core machines
VERSION 2.0 individual apps and for complete loaded with several gigabytes of
DESKTOP Xfce distributions. But the recent advent RAM or even a dedicated graphics
Does the second version of the distro of feature-rich resource-hungry card. However, chances are their
does enough to justify its title?
software has reinvigorated efforts hardware isn’t supported by the
to put those old, otherwise obsolete latest kernel, which keeps dropping
WattOS machines to good use. support for older hardware that is
URL www.planetwatt.com For a long time the primary no longer in vogue, such as dial-up
VERSION R8 migrators to Linux were people modems. Back in 2012, support
DESKTOP LXDE, Mate, Openbox who had fallen prey to the easily for the i386 chip was dropped from
Has switching the base distro from exploitable nature of proprietary the kernel and some distros, like
Ubuntu to Debian made any difference? operating systems. Of late though CentOS, have gone one step ahead
we’re getting a whole new set of and dropped support for the 32-bit
SparkyLinux users who come along with their
healthy and functional computers
architecture entirely.
URL www.sparkylinux.org
VERSION 3.5
that just can’t power the newer New life
DESKTOP LXDE, Mate, Xfce and others release of Windows. In addition to pruning the resource
Multiple flavours with different desktops Plenty of hardware is good requirements of mainstream
– is there one for you? enough to run the mainstream software, a large number of open
Linux distros without any issues. source developers are working to
However, the modern Linux desktop make obsolete hardware usable
LXLE is a fairly resource hungry beast again. There are lightweight apps
URL www.lxle.net as well, and your hardware might that consume a fraction of the
VERSION 14.04 not have enough juice to power resources of their full-featured
DESKTOPLXDE
Unity or Gnome 3. In addition to alternatives and distros that
What can this Lubuntu-based distro do
users who have hardware that’s perform blazingly well on low-spec
that its parent cannot?
been outdated fairly recently, there’s machines. In this group test we
another kind who are holding on look at some of the best distros
TinyCore to their workhorses from the last that are designed from the grounds
URL www.tinycorelinux.net decade. They usually just use their up to use the meagre hardware
VERSION 5.4 computer to browse the web, do resources on dated computers.
DESKTOP FLWM
Will it live up to its name? DATING HARDWARE
Defining hardware as “older” is tricky. onboard graphics. A couple of years
New software is always levering on the ago, mainstream distros would perform
Slacko Puppy pace of hardware developments and adequately on these machines, but not
rendering even relatively newer anymore. Nowaday, you need special
URL www.puppylinux.org
hardware obsolete. Examples of these purpose distros to make good use of
VERSION 5.7 relatively recent attic-ready hardware such hardware. We tested these distros
DESKTOPJWM would be single-core or dual-core AMD on a 1.6GHz Intel Atom netbook with
It’s the leading distro for old computers, Athlons and Intel Pentiums with about 1GB of RAM and on a dual-core 2.1GHz
but can it win this challenge as well? 1GB of RAM that they share with laptop with 2GB of RAM.
56 www.linuxvoice.com
LIGHTWEIGHT DISTROS GROUP TEST
Lightweight alternatives
T
here are two things that are developed. Other featherweight contenders than Unity, Gnome 3 and KDE 4. LXDE and
common to every lightweight distro include the Midori web browser, Xpdf PDF Xfce are two of the popular options that are
-- a lightweight desktop environment viewer, Fotoxx image editor, CMPlayer media used by many distros. There’s also Mate,
and/or lightweight apps. There are player, and App Grid software centre, among which is a continuation of Gnome 2. Then
lightweight alternatives for every type of others. Some distros, most notably Puppy there’s Enlightenment, which includes some
software. Office apps, such as the AbiWord Linux, also replace the stock apps with bling as well. Some distros, instead of using
word processors and the Gnumeric custom ones optimised for the minimal a full-fledged desktop environment, just use
spreadsheet, are a popular replacement for environment they are running under. window managers such as Openbox. Other
mainstream full fledged suites like Similarly, there are also desktop lighter but esoteric window manager are
LibreOffice and Calligra and are still being environments that are lighter on resources IceWM, Fluxbox, FVWM, and JWM.
WattOS R8
Desktop computing for cheap.
F
or a long time WattOS delivered the
goodness of Ubuntu to low-powered
machines. However, the distro has
now switched to Debian and is based on the
current stable Wheezy branch. It’s available
in three flavours: there’s one with the Mate
desktop and another with LXDE, which both
weigh in at around 800MB. There’s also an
even lighter Microwatt edition.
Being based on Debian, installation duties
are handled by Debian’s graphical installer,
which is pretty simple and straightforward.
The WattOS developers have modified the
installer with tips borrowed from the LMDE
and Point Linux projects, but it still isn’t as
intuitive as Ubuntu’s Ubiquity installer, with a
manual partitioning step that might confuse
new users. Once installed the distro
occupies about 3GB of hard disk space.
Both the LXDE and the Mate flavours ship
with the Iceweasel browser, which is Debian’s
trademark-stripped fork of the Firefox
browser. Both flavours also include the The distro also includes power management utilities like PowerTOP to optimise power consumption.
Shotwell image organiser, FileZilla FTP,
Transmission BitTorrent client, Audacious Both distros were quick off the blocks and sports the conky system monitor and a
audio player and Xfburn media burner. The we got to the desktops pretty quickly with simple panel at the bottom of the screen
LXDE flavour also includes the VLC media Mate leading LXDE by a good 10 seconds. that houses open windows.
player, which is oddly missing from the Mate Once loaded though LXDE took up about The developers have done a wonderful job
version. 100MB less RAM than the fast-booting in picking up the right apps that don’t gorge
Mate. App launch times were fairly similar on resources and don’t compromise
Missing in action and both flavours performed as advertised. usability as well. While the distro might be
One app that was conspicuous by its Even after several hours their memory designed for older computers, we wouldn’t
absence was an office suite. All you have are footprints remained impressively low. shy away from recommending it as a lighter
basic text editors -- Mate has Pluma and If you want something lighter still, there’s Debian alternative for regular use.
LXDE has Leafpad, and these are both quite the Microwatt edition. Instead of a full-
stripped down. On the upside though you fledged desktop manager, this flavour uses a VERDICT
A wonderful distro that
have the full Debian repository at your customised Openbox window manager in could put a spring in the
disposal that you can install additional apps place of the PekWM window manager in step of any computer.
from via the Synaptic package manager. earlier versions. The bare-minimum desktop
www.linuxvoice.com 57
GROUP TEST LIGHTWEIGHT DISTROS
Linux Lite 2.0
Can lite be right?
T
he Linux Lite distro is based on (it’s also preconfigured here to connect
Xubuntu 14.04 LTS, which to the LinuxDistroCommunity.com’s
brings along two very important Mumble server, so you can engage with
components -- Xfce 4.11 and the other community users immediately.
excellent and easy-to-handle Ubiquity Another unique aspect of the distro is
installer. One of the first things you’ll its collection of well-designed scripts to Linux Lite is wonderfully stocked for everyday use, but this
notice after installation is the distro’s add and remove programs. The Install comes at the cost of relatively sluggish performance.
beautiful login manager followed by the Additional Software script gives a list
aesthetically pleasing all-white theme. of 25 apps, including Google Chrome Ubuntu 14.04’s official repository as
The desktop is clean and uses the Xfce and Chromium browsers, Google Talk well as several PPAs. This is also the
desktop’s Whisker menu. The Browser Plugin to video chat via Google first release which uses the Linux
developers have tweaked the desktop, Hangouts, Dropbox, Netflix, Skype, Wine, Lite’s own repositories for managing
and the right-click menu includes PlayonLinux, and more. There’s also a its custom apps. One of these custom
options to create shortcuts, launch the corresponding Remove Software script apps, the Lite User Manager, helps make
task manager, and take screenshots. that’ll remove any software installed managing accounts a little easier for
At first glance, Linux Lite looks and using the previous script. new users to comprehend. New users
feels like a regular heavy-duty distro. There’s also the Synaptic package will also appreciate the bundled support
The list of pre-installed apps doesn’t manager and the distro is tuned into and help manual.
include any of the traditional lightweight
apps and is instead brimming with the
usual suspects such as Gimp, Firefox,
“One unique aspect of Linux VERDICT
A good distro for
VLC and LibreOffice. There’s also the Lite is its collection of scripts someone who’s new to
Linux, but not necessarily
Mumble open-source VoIP software
that’s often compared with TeamSpeak
to add and remove programs.” lite.
LXLE 14.04
Luxuriously light.
T
here’s a lot of similarity between as its terminal emulator rather than
Linux Lite and LXLE. Both are Lubuntu’s LXTerm.
based on the latest Ubuntu The distro is overflowing with apps.
14.04 LTS release and neither include Besides the usual apps such as Gimp,
any of the usual lightweight apps, Shotwell, Claws email, FileZilla, Pidgin,
instead relying on their desktops. In that Transmission, LibreOffice, there are The distro includes a whopping 100 wallpapers, and you
aspect, LXLE, which is based on several unusual ones like KeePassX, can cycle through them with a button in the bottom panel.
Lubuntu and uses the LXDE desktop Marble, Anki memory training, Simple
scores over Linux Lite by trimming Image Reducer, BitTorrent Sync, Gitso includes both the Lubuntu Software
almost 10 seconds of the latter’s boot VNC, Linphone, Homebank, Osmo, FB Center, which is LXDE’s answer to the
time. However, installing LXLE takes a Reader ebook reader, BleachBit, Florence Ubuntu Software Center, as well as
lot longer than other distros. But that Virtual Keyboard, and the GSpeaker Synaptic. Both are configured to fetch
isn’t a surprise considering it installs frontend for espeak. packages from the official Ubuntu
almost 2,000 packages. In stark contrast to many of its repos and several other PPAs. LXLE
The desktop is a pretty standard peers, the distro also includes several also includes a graphical PPA manager
LXDE affair. It includes a panel at the multimedia apps such as Audacity, using which you can add and manage
bottom and a Unity-like launcher on Arista transcoder, the Openshot video additional PPAs.
the left that reveals itself when you editor and Minitube for watching
mouse-over that part of the desktop. YouTube videos on the desktop. VERDICT
Some important information about the Another pleasant surprise is the Despite its long list of
apps, the distro performs
system is also displayed on the desktop inclusion of several games, from simple well on hardware with
via the Conky system monitor. However, card games to the Steam client. For limited resources.
the distro uses the malleable ROXTerm package management, the distro
58 www.linuxvoice.com
LIGHTWEIGHT DISTROS GROUP TEST
SparkyLinux 3.5 Other options
Give your computer a jump start.
The low-fat graphical options
that aren’t necessarily aimed
at older hardware
T
here are several other distros that use
the lightweight desktops that are often
included on the distros we’ve tested
here, not because of their size benefits, but for
their similarity to the classic desktop
metaphor, such as the Mate-powered
Debian-based Point Linux.
Another lightweight distro is Elementary
OS, which uses its own custom desktop
environment along with a host of other
custom tools, and is popular for its Mac
OS X-like look and feel. However, the distro
is designed primarily as a replacement for
SparkyLinux includes the SparkyCenter settings manager to house its custom apps. Windows and Mac, and wouldn’t perform well
on dated hardware.
U
nlike other Debian-based distros Being based on Debian, the distro also Some distros – most notably Ubuntu
in this group test, SparkyLinux is includes Debian’s forked trademark-free – have official spins based on LXDE and
based on the distro’s testing version of Firefox and Thunderbird, namely Xfce, namely Lubuntu and Xubuntu, that are
branch (called Jessie) and also borrows IceWeasel and IceDove. The browser is designed for hardware that doesn’t have the
Debian’s installer. SparkyLinux is available equipped with plugins to handle all kinds power to run the main edition. There’s also
in several flavours, each based on a of content including Flash, QuickTime, Trisquel Mini (a cut-down version of Trisquel,
separate lightweight desktop DivX, RealPlayer and more. the distro made entirely with free software –
environment. While the size of the ISO even the non-free elements of the Linux kernel
image and the number of installed Shiny desktops have been removed) for the free software
packages vary from one flavour to The Enlightenment flavour uses the latest purists, and VectorLinux Light, which uses
another, installing them all took longer E19 desktop. However, the live JWM and Fluxbox. Another distro that uses
than the other distros in this group test. environment performed terribly on the Fluxbox is the Debian-based AntiX, which also
Another common factor between all netbook and took aeons to install. Even relies heavily on custom tools.
the SparkyLinux flavours is its collection afterwards moving the mouse wasn’t The SliTaz distro also uses a bunch of
of custom apps. There’s the SparkyAPTus smooth and animations were jerky; so, the custom tools but needs to be configured and
app, which is a simple front-end to the Mate, LXDE, and Xfce flavours are the set up before it can be used as a functional
command line apt-get and dpkg tools. distro’s leading contenders. You can use desktop. Finally, there’s Porteus, which
You can use this tool to edit the package them in various languages and they all is primarily designed for installation on
repositories, install and remove apps and have a similar looking desktop with the removable mediums like USB disks and CDs,
upgrade the whole system with a single Conky system monitor and the Wbar quick- but can also be installed on to a hard disk. The
click. SparkyAPTus Extra is a new app with launch dock at the bottom. distro is small because of its modular nature
which you can install popular apps such The distros are also loaded with and incredibly fast since it runs from the RAM,
as Dropbox, Skype, Steam, Tor Browser, and apps including LibreOffice, PlayonLinux, but it does involve a learning curve.
more with a single-click. Gimp, Camorama webcam, Hotot Twitter
The distro also includes custom apps client, gFTP, Pidgin, Gnome MPlayer,
to back up and restore app settings. RecordMyDesktop screencaster, VLC media
All you have to do is select the app and more. For system admins there’s
whose settings you wish to you wish to GParted, Boot Repair, a graphical front end
back up, and the app saves them in a to manage systemd and a graphical front
compressed archive. You can then use end to install windows wireless drivers via
the complementary Restore app to point Ndiswrapper and the Gufw firewall.
to this archive to restore the settings.
There’s also an app to securely and VERDICT
permanently delete files, a Wine wrapper Performs admirably well
on resource-deprived
to install Windows .exe files, a manager computers despite its Check out PepperMint Linux if your bandwidth is
for the Conky system monitor and tools to gamut of apps. good enough that you can live off web apps.
manage users and passwords.
www.linuxvoice.com 59
GROUP TEST LIGHTWEIGHT DISTROS
TinyCore 5.4 vs Puppy Linux 5.7
The most esoteric distros of the lot.
T
hese two distros are arguably intuitive in the business. You’ll also have
our first choice for powering to browse through its documentation
computers that are light on to familiarise yourself with the distro’s
resources. However, both distros are peculiarities, irrespective of your
designed for advanced users, TinyCore experience with Linux.
more so than Puppy. Also, while both
distros will revive literally any computer, Puppy Linux
their approach to addressing the Puppy Linux’s approach is in stark
problem is different. contrast to TinyCore. The project
TinyCore’s sole developer, Robert currently has three official versions.
Shingledecker was earlier involved There’s Wary Puppy, which is designed
with the once-popular but now- especially for older hardware, followed
dormant Damn Small Linux project. by Lucid Puppy, which is built from TinyCore includes a remaster tool with which you can
The distro is available in three flavours. Ubuntu’s binary packages; and Slacko create your own remix of the distro.
There’s a miniscule 9MB core edition Puppy, built from Slackware. Slacko is
designed for servers, followed by the recommended distro and the can perform with a desktop computer.
the recommended TinyCore edition current 5.7 is built on of Slackware 14. However, most of these are Slacko’s
that weighs in at 15MB, and a 72MB Instead of a full-fledged desktop own custom apps instead of the
CorePlus edition that has additional manager, Slacko uses JWM, which popular ones that users are familiar
drivers for wireless cards, a remastering is one of the lightest window with. Slacko has all kinds of multimedia
tool and internationalisation support. managers. Installation is handled apps include graphics viewers and
True to its name, TinyCore bundles by Puppy’s custom installer, which creators and apps to playback, edit and
just a terminal, a text editor, and an is well documented but has enough even create multimedia. Furthermore
app launcher on top of the light- peculiarities to intimidate first-time there are apps to block website ads
weight FLWM window manager. It users. For starters it lacks any and for internet telephony, a podcast
has a control panel to manage bootup automated partitioning tool and grabber, a secure downloader, a DVD
services and configure the launcher. instead fires up GParted for the user to burning app and lots more. The distro
If you need anything else, you’ll have manually format the disk.
to pull it in using the distro’s package
manager, including the installer if you
To its credit though, GParted is very
verbose and each step has enough “There’s no beating Puppy
want to install the distro full-time on to documentation for the user to carry Linux Slacko for out-of-the
box functionality.”
your hard disk. out the task at hand. Also, once the
Due to its minuscule size, TinyCore installation has completed, users will
boots blisteringly quickly. But the have to manually invoke a tool to install
distro’s stellar performance comes at the Grub bootloader. ships with several multimedia players,
the price of usability. For starters, you’ll There’s no beating Puppy for out- including Gnome MPlayer, to play all
be spending quite a lot of time with its of-the-box functionality and there’s an sorts of media formats. The included
package manager, which isn’t the most app for virtually every task that you Firefox browser is equipped with all
kinds of plugins and the distro also has
a custom app to download and install
the Flash plugin.
Puppy also scores for its ample
documentation. Slacko bundles help
documentation on several topics
such as working with Microsoft Office
files, how to add codecs, software
and more and contains links to the
documentation pages for most of the
apps in its menus.
VERDICT
TinyCore: Ideal for all Slacko Puppy: One of
kinds of hardware but the lightest around, but
setting it up is an loses out for relying on
involved process. its custom apps.
Puppy is very explicit in its instructions and verbose in its output.
60 www.linuxvoice.com
LIGHTWEIGHT DISTROS GROUP TEST
OUR VERDICT
1st Sparky Linux 3.5 Mate
Version 2.0
www.sparkylinux.org
The perfect balance of speed and functionality in this Mate
powered distros that’s chock-full of apps.
Lightweight distros 2nd LXLE 14.04
Version R8
I
f this were a group test of which is almost twice that of www.lxle.net
distros specifically for older the winner. However, if you have A close second to Sparky Linux and the best lightweight distro
hardware, then Slacko Puppy the RAM to spare, then LXLE is based on the LXDE desktop.
would have been top dog followed our favourite LXDE-based distro
by TinyCore, which is lighter but has around and it’s even faster than
a more involved setup process. SparkLinux’s LXDE flavour. 3rd Linux Lite 2.0
However, the real test of a Version 3.5
lightweight distro is on a machine Sparktastic
www.linuxliteos.com
that’s not necessarily old, just not SparkyLinux is available in a
The distro works well to free up resources on newer machines
adequately stacked. This is why we number of editions with almost but doesn’t feel comfortable on older ones.
rated the distros based on their every lightweight desktop
performance on the dual-core environment and window manager.
netbook, and the table below But the performance varies greatly 4th WattOS R8
reflects numbers as measured on between its various editions. The Version 14.04
this computer. Enlightenment edition is fastest but
WattOS Mate edition was quick lacks any real apps, and also felt www.planetwatt.com
The Mate edition of this distro boots faster than all others but
off the blocks, but lacked any lethargic, much like the Xfce flavour.
lacks any meaningful apps.
useful apps. The LXDE edition of The mouse movement on both
the distro does include VLC but editions was jerky, and navigating
loses snappiness. We’ve rated through the menus wasn’t smooth 5th Slacko Puppy 5.7
it lower than the slow-starting with the sub-menus revealing Version 5.4
LinuxLite because at least the latter themselves only after a brief pause.
welcomes the user to a much The Mate and LXDE editions www.puppylinux.org
richer desktop experience. In fact, were very usable and highly Our favourite distro for revising older computers, but it loses
out in this challenge for its reliance on its custom apps.
LinuxLite would be a good distro to recommended. On these editions,
introduce new users to Linux. you could further trim the boot
This group test would have easily times by tweaking some defaults, 6th TinyCore 5.4
been won by LinuxLite. It’s one like disabling the Wbar panel at the Version 5.7
of the fastest distros and loads bottom. Even without any tweaks,
to a very usable desktop straight the Mate edition of the distro offers www.tinycorelinux.net
out of the box. But it loses out to the right compromise between boot The lightest Linux distribution of them all, it loses out for its
involved setup process.
SparkyLinux despite being faster times, memory footprint and pre-
because of its memory usage, installed apps.
Boot time Used memory Total Packages Desktop Environment Package Management Office Suite Multimedia app
Linux Lite 2.0 41.2s 501 MB 1389 Xfce 4.11 Synaptic LibreOffice VLC
WattOS R8 Mate 14.6s 332 MB 1125 Mate 1.8 Synaptic None None
WattOS R8 LXDE 23.4s 231 MB 1118 LXDE 0.5.5 Synaptic None VLC
LXLE 14.04 34.5s 775 MB 1931 LXDE 0.5.6 Synaptic LibreOffice Several
Tiny Core 5.4 7.5s 46 MB --- FLWM Custom None None
Slacko Puppy 5.7 17.2s 112 MB 333 JWM Custom AbiWord, Gnumeric Gnome Mplayer
Sparky Linux 3.5 e19 31.6s 285 MB 1267 Enligtenment e19 Synaptic None None
Sparky Linux 3.5 Mate 37.2s 357 MB 1894 Mate 1.8 Synaptic LibreOffice Several
Sparky Linux 3.5 LXDE 41.3s 342 MB 1994 LXDE 0.5.5 Synaptic LibreOffice Several
Sparky Linux 3.5 Xfce 38.2s 418 MB 2019 Xfce 4.10 Synaptic LibreOffice Several
www.linuxvoice.com 61
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CORETECHNOLOGY
CORE
A veteran Unix and Linux
enthusiast, Chris Brown has
written and delivered open
source training from New Delhi
to San Francisco, though not on
TECHNOLOGY
the same day. Prise the back off Linux and find out what really makes it tick.
Access control
Get to grips with file access controls in Linux as we take “rwx” to the max.
C
heck into a hotel, and the chances In my list, items 2 and 3 are implemented meaning of these three permissions as
are you’ll get a little plastic card. Take by rules in userspace (ie within the code of applied to files and directories. The meaning
the lift to your room, slot the card in the server itself), whereas items 1 and 4 rely of the execute bit, in particular, is totally
the door, and either it will let you in or you will on decision-making code in the kernel. different for files and directories. You should
have to retrace your steps to the check-in It’s the bottom layer (item 4 – file access also notice that you need to have both read
desk to get a new card. That’s access control) that I want to focus on here. The and execute permission to have any sort of
control. Within an operating system, it can detail of how this works is a well-travelled useful access to a directory, and they
be applied at various points. Consider the road and probably familiar to you. But I’ll try invariably go together; you are very unlikely
common scenario of browsing to a website to turn over a few stones along the way that to come across a directory that has one but
that’s delivered by a LAMP stack. Access you haven’t looked underneath before. not the other.
controls are applied at several places in the This is pretty basic stuff. “Sure”, I hear you
data path: Burn after reading say. “I knew all that”. But do you really
1 Packet filtering rules in the Linux kernel A good place to start is by examining a understand how it works? Consider this:
can block incoming traffic except to a few couple of lines from ls -l: $ ls -l test
favoured ports, or from a favoured IP # ls -ld /home/chris /etc/shadow -r--rw-rw- 1 chris chris 0 Sep 19 16:10 test
address range perhaps. -rw-r----- 1 root shadow 1284 Sep 29 13:51 /etc/ My question is, can I (chris) as the owner
2 The Apache web server can apply access shadow of the file, write to it? Before you read on,
controls based on directives in its config drwxr-xr-x 93 chris chris 4096 Sep 29 12:08 /home/ have a guess!
file. For example, “allow from” and “deny chris Then try this:
from” rules control access based on the The first field of the line includes the $ echo hello > test
client machine identity, and it also classic nine permission bits, the third and bash: test: Permission denied
supports user logins to restrict access to fourth fields show the owner and group of …which will convince you that you can’t. It
parts of the site to specific authenticated the file. The table ‘rwx explained’ shows the is tempting to think that because members
users. Many servers such as Samba and
Postfix can impose similar rules.
3 The PHP code on a web page queries a
Create a shared directory
back-end database, probably MySQL. Here Our mission here is to create a directory that can Now make sure that andrew and graham are
again, there’s a need to authenticate, and be used as a shared read/write resource by two members of the group (we assume they already
there’s a fine-grained set of privileges users: andrew and graham. We will accomplish have accounts):
this by making them both members of the group # usermod -a -G editors andrew
defined in MySQL’s grant tables. “editors”, and the directory will be /home/editors. # usermod -a -G editors graham
4 Underneath it all, we have the Linux
First, create the group: Finally, establish a umask of 007 for andrew and
filesystem. Again, access control decisions # groupadd editors graham by adding a line:
are made based on the file’s ownership Now create the directory and set its group. Then umask 007
and permissions, and on the identity of the set its setgid bit so that files created here will have in the ~/.profile file of the two users. This will
the group “editors”: ensure that files they create are accessible by the
process attempting the access. # mkdir /home/editors group but not by others. Allowing the files they
Indeed, there are so many points along # chgrp editors /home/editors create to be group writable is OK because outside
the way at which something might say “no” # chmod g+ws,o-rwx /home/editors of /home/editors any files they will create will have
that it’s a miracle it ever works at all. And It should now look like this: their regular primary group (andrew or graham)
don’t even get me started on the mandatory # ls -ld /home/editors and only the accounts andrew and graham will
drwxrws--- 2 root editors 4096 Sep 29 20:38 /home/ have membership of those groups. For more on
access control mechanisms like SELinux editors umask, see Command Of The Month.
and App Armor.
64 www.linuxvoice.com
CORETECHNOLOGY
of the file’s group (and for that matter
everyone else) have permission to write to The rwx permissions: files vs directories
the file, then you should too. But it doesn’t Permission On a file On a directory
work that way. If I am the owner of the file, I r (read) Read the file. (Make a copy of List the names of the files in a
see the first set of permissions. End of story. it, display it, compile it.) directory.
The tests are not applied in a hierarchical
way. In practice this situation almost never w (write) Write to the file. (Edit or Create file (links) in the
append to it or copy over it.) directory, or remove them.
arises. It is very rare (and not particularly
useful) for the permissions to become x (execute) Run the file as a command. Access the files in the directory,
more liberal as you move from left to right (Applicable to compiled use the directory in a pathname.
(owner/group/other). It’s usually the other programs or to scripts.)
way round.
The other interesting question is “Can the
owner (chris) delete the file?” Have another known as the “set user ID bit”, the “set group the effective privileges of its owner – in this
guess, then try this: ID bit”, and the “sticky bit” which are less well case root. The program is said to run “setuid
$ rm temp1 understood. The “set user ID” bit (setuid to to root”. As root, of course, it can do
rm: remove write-protected regular empty file its friends) is probably the most interesting, anything, including writing to the shadow
‘temp1’? yes and by way of introducing it, consider these file. Once the program terminates, you’re
$ three facts: back to your normal identity at the shell
You will get a warning from rm about 1 Passwords in Linux are stored in a file prompt. This mechanism lies at the heart of
deleting a file on which you don’t have write called /etc/shadow. (Actually, it’s the all “privilege escalation” events in Linux. It’s
permission, but if you answer ‘yes’ it will do password hashes that get stored.) how commands like su and sudo work, for
it. The point is this: whether you can delete a 2 The shadow file is heavily protected example. It’s also used by programs like
file does not depend on the permissions on -- ordinary users can neither read or write ping, not because they need to elevate their
the file itself; it depends on the permissions to it. access into the file system, but because
on the directory you’re trying to delete it from 3 Users can change their passwords they need to reach right down to the IP layer
(you need write permission). This is logical if without administrative help. and construct unusual network packets,
you think about it – we’re not actually trying So how does this work, exactly? The which only root processes can do.
to write to the file, we’re just trying to write to following commands give us a clue: The setuid bit was invented by the late,
the directory (to remove the link). But in the $ which passwd great Dennis Ritchie while he was working
training classes I run I usually see a few /usr/bin/passwd for Bell Telephone Laboratories. They
raised eyebrows and wrinkled noses when I $ ls -l /usr/bin/passwd obtained a patent (US patent 4135240 –
explain this. The fact is, there is no “you can -rwsr-xr-x 1 root root 47032 Feb 17 2014 /usr/bin/ look it up of you’re interested) though they
delete me” file permission in Linux. passwd never charged licensing fees and later
The warning you receive from rm in this The thing to notice is the s in the fourth placed the invention into the public domain.
case is not characteristic Linux behaviour. character position, where the x would Interestingly, the operation of setuid was
The usual philosophy of these commands is normally be. This is the famous setuid bit. explained on the patent by a diagram of
“if you asked to do it, and if you have Let me explain. logic gates and signals, it being unclear at
permission to do it, I’ll do it”. For example, if If a file is executable, and it has the setuid the time whether a software algorithm could
you have files foo and bar, neither of these bit set, then while it is running it runs with actually be patented.
commands will raise a query:
$ cp foo bar
$ mv foo bar Firewall Access control Login and
even though both of them will result in the
rules directives privilege grants
loss of the original file bar.
The nine “rwx” mode bits on a file are well
known, but there are actually three more, Apache MySQL
web database
server server
Fool your boss!
Do you have to contend with an insufferable
Linux know-it-all at work? Would you like to
outsmart them? Then try this:
$ touch temp File access
$ chmod 7000 temp permissions
$ ls -l temp
---S--S--T 1 chris chris 491 Jun 30 15:49 temp Filesystem
Ask them to do an ls -l on the file then
explain the permissions. Of course, there’s a
small risk that they’ll actually know, in which
case they’ll become even more insufferable! Linux applies access control at several points within a LAMP (Linux, Apache, MariaDB/MySQL,
PHP/Perl/Python) stack, some in the kernel and some in userspace.
www.linuxvoice.com 65
CORETECHNOLOGY
Finding out who you are
We can demonstrate the effect of the setuid bit with No surprises here. 1000 is the UID of my regular $ sudo u-s uiddemo
a trivial C program using the getuid() and geteuid() account. Now try this: Now wrap the program in a tiny shell script
system calls, which report on the real and effective $ sudo chown root uiddemo called uuidemo-bash like this:
UID of the process respectively. Here’s the code: $ sudo chmod u+s uiddemo #!/bin/bash
#include <stdio.h> $ ls -l uiddemo ./uiddemo
main() -rwsrwxr-x 1 root chris 8620 Sep 28 18:52 uiddemo and make the shell script itself run setuid to root:
{ $ ./uiddemo $ sudo chown root uiddemo-bash
printf(“Real ID = %d\n”, getuid()); Real ID = 1000 $ sudo chmod u+s uiddemo-bash
printf(“Effective ID = %d\n”, geteuid()); Effective ID = 0 $ ls -l uiddemo-bash
} Now that the program is running setuid to root, it -rwsrwxr-x 1 root chris 24 Sep 28 18:57 uiddemo-bash
I won’t insult your intelligence by dissecting this! reports an effective UID of zero, and at this point, it $ ./uiddemo-bash
Now compile and run it: is all-powerful. Real ID = 1000
gcc uiddemo.c -o uiddemo The setuid bit is not honoured on shell scripts. To Effective ID = 1000
$ ./uiddemo demonstrate this, begin by resetting the ownership The output shows clearly that the script is owned
Real ID = 1000 and mode of uiddemo back to what it was: by root and has the setuid bit on; nonetheless, no
Effective ID = 1000 $ sudo chown chris uiddemo privilege change has occurred.
Programs that run setuid to root need to system to keep it loaded in memory after format from ls -l to consider changing it
be coded with great care to avoid design use, thus speeding things up the next time it now. The assumption is that the ‘x’ bit that’s
flaws, buffer overflows, or other was run. These days, a program’s code is underneath is set (for example it doesn’t
vulnerabilities which would put them at risk paged in as part of the virtual memory make sense to set the setuid bit on a file if
of being subverted. management, and the sticky bit’s original it’s not executable). If the underlying ‘x’ isn’t
You can find all the setuid programs on role has long been redundant. It has, set, you’ll see an upper-case S or T instead
your system with the command: however, found an important retirement job (see the box “Fool your boss!”) but you need
$ sudo find / -user root -perm +4000 -ls when applied to directories. to be pretty eagle-eyed to spot this.
Hopefully, you shouldn’t find too many. As we have seen, you can delete any file if
And if you claim to be a security-conscious you have write permission on the directory The scoop on groups
system adminstrator, you really ought to be you’re deleting it from. This doesn’t work too Every user has a primary group. The primary
able to say what all of them are for. well for world-writable directories (/tmp is group assigned to them when they log in is
The “set group id” (setgid) bit is similar. the obvious example; you may find a few taken from the fourth field of /etc/passwd.
Whilst the program is running, it runs with others) because you would be able to delete On many systems, adding a user account
the effective group of its owner. Again, find other peoples’ files. The sticky bit changes will, by default, add a new group with the
will locate these for you: the rules so that you can only delete files same name, so that each user has a
$ sudo find / -perm +2000 -ls that you own. personal primary group that only they
You’ll probably see quite a few The way that ls -l shows you these three belong to.
administrative group ownerships showing extra bits (putting an s or t over the top of However, it’s easy to create new groups and
up in this list. Running setuid is potentially the ‘x’ bits) is confusing to say the least. It assign a user any primary group of your
more dangerous than running setgid, and would have been better, perhaps, for ls to choice when you create their account. A
running setuid to root is most dangerous of squander three more character positions on user can also have a number of secondary
all. But using setgid effectively takes more the line to represent them explicitly, but I group memberships. These are defined in
thought about setting file groups and guess there are too many scripts out there /etc/group. For example, if you see this line
permissions. And sometimes setuid-to-root that make assumptions about the output in /etc/group:
is necessary to get the job done.
The setgid bit has a totally different
meaning when applied to a directory.
Octal values
Normally, when a file is created, its group is
4000 2000 1000 400 200 100 40 20 10 4 2 1
taken from the primary group of its creator.
However, if the file is being created in a r w x r w x
directory that has the setgid bit set, the s g t r w x
group will be inherited from that of the
directory. (This obscure feature makes a Group “Rest of world”
wonderful Linux interview question, by the sticky Owner permissions permissions
way!) See the box Create A Shared Directory bit permissions
for an example of how to exploit this feature.
setgid
The sticky bit setuid
In the very early days of Unix, the “sticky bit”
would be set on a frequently used
executable to encourage the operating Every file and directory carries these 12 access control bits; each can be identified by its octal value.
66 www.linuxvoice.com
CORETECHNOLOGY
editors:x:1002:andrew,graham
then andrew and graham have “editors” as a The three “extra” mode bits -- less well known but very important
secondary group. Permission On a file On a directory
You can create a new group like this: s (setuid) Run an executable file with Unused
$ sudo addgroup editors the effective user privilege of
Adding group `editors’ (GID 1002) ... its owner
Done.
And you can give a user secondary group g (getuid) Run an executable file with Files created in this directory
the effective user privilege of will inherit their group from the
membership like this:
its group group of the directory
$ sudo usermod -a -G editors andrew
When a user creates a file, the file’s group t (sticky bit) Unused Only allow users to delete files
is normally set to the user’s primary group from this directory if they own
(for an exception to this see the box Create A the file
Shared Directory). When a user accesses a
file that he’s not the owner of, if the file’s
group matches any of the user’s groups, This command starts a new shell with the # gpasswd hackers
(primary or secondary) then he’ll see the new primary group identity. (And by the way, Changing the password for group hackers
group permissions on the file. In effect, you newgrp runs setuid-to-root to allow it to do New Password:
are “in” all your groups simultaneously. this.) The following sequence of commands Re-enter new password:
shows newgrp in action. Assume andrew The password hashes are stored in
Move users around has just logged in, and pay attention to the /etc/gshadow, analogous to /etc/shadow
So for example, user andrew with primary group of the files f1 and f2: for user passwords. Now, if andrew tries to
group “andrew” and secondary group $ touch /tmp/f1; ls -l /tmp/f1 make hackers his primary group, although
“editors” will be able to read the file -rw-rw-r-- 1 andrew andrew 0 Sep 29 14:33 /tmp/f1 he’s not a member, he’ll succeed if he knows
/tmp/target with ownership and $ newgrp editors the password:
permissions like this: $ touch /tmp/f2; ls -l /tmp/f2 $ newgrp hackers
$ ls -l /tmp/target -rw-rw-r-- 1 andrew editors 0 Sep 29 14:33 /tmp/f2 Password:
-rw-r----- 1 root editors 24 Sep 29 13:47 /tmp/target You can set a password on a group, $ id
It’s also possible for a user to switch his though hardly anyone uses this feature. If uid=1001(andrew) gid=1004(hackers) groups=1001(
primary group to be any of his secondary you do, a user can make any group his andrew),1002(editors),1004(hackers)
Be aware, though, that telling someone
the password for a group is not the same as
“It’s possible for a user to switch his primary group making them a member of the group.
to be any of his secondary groups.” Although file permissions are not the only
place that Linux applies access controls,
they are absolutely essential to system
groups, though this feature is rarely used in primary group as long as he knows the security. In my experience a high proportion
my experience. So, for example, andrew can password. Let’s try. First, we’ll add a new of system problems or security holes come
switch his primary group to be “editors”, like group called “hackers”: down to misunderstanding or misapplying
this: # groupadd hackers file permissions. Knowing how they really
$ newgrp editors Now we’ll set a password on it: work is important.
Command of the month: umask
Strictly speaking, umask isn’t a command, Now if we create a directory and check its drwxr-x--- 2 andrew andrew 4096 Sep 29 21:20 test2
it’s a shell built-in, but I don’t mind thinking of permissions we see something like this: We see that the bits that are set in the
it as a command if you don’t. The umask $ mkdir test1 umask (we might represent it as ----w-rwx)
setting (usually established in a shell startup $ ls -ld test1 are NOT set in the file’s permissions. To be
file such as ~/.profile) is used to limit the drwxrwxrwx 2 andrew andrew 4096 Sep 29 21:20 exact, to compute the permissions that will
permissions that will be assigned to any file test1 be assigned to a file when it is first created,
you create. It’s a bit confusing because it Notice the very liberal permissions on the take the one’s complement of umask and
sort of works ‘upside down’ – the directory. Now let’s tighten things up by perform a bit-wise logical and operation with
permission bits that are set in umask will be setting a umask and repeating the the permissions requested by the program
withheld from any files you create. experiment: that created the file. Also, you should
Maybe a couple of examples will help. $ umask 027 understand that umask only takes effect at
First we’ll set our umask to zero: $ mkdir test2 the instant a file or directory is created. It
$ umask 000 $ ls -ld test2 doesn’t apply retrospectively to existing files.
www.linuxvoice.com 67
FOSSPICKS
FOSSpicks Sparkling gems and new
releases from the world of
Free and Open Source Software
Mike Saunders has spent a decade mining the internet for free
software treasures. Here’s the result of his latest haul…
Partition manager
GParted 0.20
V
ersion numbers are funny The latter is what we’re looking at
things. Some developers here, as it’s very useful to have
would argue that they don’t around on a spare CD-R or USB key
mean much, but end users often for emergencies.
infer a lot from them. We know of The ISO weighs in at a touch
quite a few FOSS programs that under 200MB, and when booted, it
have surprisingly low version asks for your keyboard layout and
numbers, given their quality and language. Then it drops you into a
feature set, such as Inkscape. It has rather ugly Fluxbox desktop, with
been around for years, has loads of some dreadful desktop icons. Sure,
features, is used by professionals glitz and fancy effects aren’t
for real work, and yet it’s only at important here, but a bit of work on
0.48. The same could be said of the presentation would be welcome,
GParted: it’s a hugely useful and especially when you’re using it to fix
mature tool, yet its 0.20 version someone else’s system.
number suggests it’s barely at Anyway, GParted itself pops up, This panel shows the range of filesystems that are supported, and
alpha stage. showing the layout of your hard operations available for them.
That might scare some users drive. (If you have multiple drives,
away, especially given its job of you can select the one you want to partition in the list to select it, and
performing (potentially risky) edit via the drop-down menu on the then use the toolbar at the top (or
filesystem operations. In our top-right of the window.) Click on a the right-click menu) to perform an
experience over the years, though, operation on it. Note that GParted
GParted is a tool you can rely on. It’s
a GTK-based program for managing
“GParted is very useful to have doesn’t perform its operations
straight away – instead, it batches
partitions on your hard drive, and around on a spare CD-R or USB them up until you click the Apply
it’s available in two flavours: as a
standalone app, or as a live distro.
key for emergencies.” button at the top.
GParted is tremendously versatile,
supporting over 20 filesystem
formats, although not every
operation is available for each
format. But for the common
formats (ext*, btrfs, NTFS, FAT32,
HFS+) you can create, copy, resize
and relabel partitions. In many
cases you can also perform checks
on partitions, and attempt to
recover deleted ones. It’s a great
toolbox for working with hard
drives, and an essential part of a
sysadmin’s armoury.
The GParted Live distro
isn’t a feast for the eyes
PROJECT WEBSITE
and looks very late 90s,
www.gparted.org
but it gets the job done.
68 www.linuxvoice.com
FOSSPICKS
Operating system
Minix
A
lthough it’s not very well parts of the system exchanging
known, Minix played a messages all the time, performance
major role in the early days can be impacted significantly. So
of Linux. It was created by the debates continue today, but
computer science professor Minix 3 is a good example of a
Andrew Tanenbaum as a learning genuinely useful all-round OS built
tool, and Linus Torvalds used it to on a microkernel design.
build the very early releases of his
kernel. The two hackers got into a A bit of this, a bit of that
fascinating online debate about Minix 3 is now regarded as an
kernel design – a debate that has alternative to Linux and the BSDs
become so famous, it even has its for embedded devices and low-spec
own Wikipedia page: http://tinyurl. hardware and it runs many FOSS
com/b2us8t. Tanenbaum argued apps you’re familiar with. To install
Minix 3 is the first
that microkernels are the future, it, you’ll need at least 64MB of RAM releases. Indeed, Minix also uses
release to support ARM
and Linux was already obsolete and an i586 or newer processor chips, and specifically NetBSD’s Pkgsrc system, so a wide
before it had even taken off. along with 675MB of drive space. BeagleBoards (image: range of software is available with
Torvalds disagreed, of course. Minix 3.3 is provided as a 288MB Mapper 07, Wikipedia). just a few commands. However, X
But what is a microkernel? compressed ISO image, which wasn’t working at the time of
Essentially, it’s a very small kernel extracts to 578MB, so it can be writing – the developers were still in
that does a handful of vital jobs: burned to a regular CD-R. After the process of moving away from
mapping memory, controlling booting, you’ll be prompted to log in the crusty old XFree86 codebase.
processes, and enabling processes as root (without a password), and Ultimately, Minix feels a lot like
to communicate with one another. then run setup to begin installation. Slackware and Debian from the
Everything else, including hardware This is all plain text, and there are no mid-90s. It’s surprisingly usable and
drivers, networking protocols and hand-holding wizards, but if you interesting to explore, and the
so forth, are run in “userspace”, have some Unix experience you documentation isn’t bad either. It
where they can’t interfere with the won’t find it too daunting. won’t be challenging Linux or
inner workings of the kernel. By and large, Minix has a familiar FreeBSD any time soon, but if
Contrast this to Linux, where a good Unix-like userland, which isn’t you’re interested in exploring
chunk of the OS’s functionality is surprising as much of it has been alternative kernels or just want to
provided directly inside the kernel. taken from NetBSD in recent expand your Unix knowledge, give it
So a microkernel should, in a go in VirtualBox or Qemu. (Note:
theory, be more reliable, as parts
can be swapped out more easily in
“Minix 3 is now regarded as an for the former, create a virtual IDE
hard drive image.)
the event of a bug wreaking havoc. alternative to Linux and the BSDs
But when you have more things
happening in userspace, and major
for embedded devices.” PROJECT WEBSITE
www.minix3.org
How it works: Installing Minix3
1 Boot 2 Install 3 Wait
You can use a real PC, but it’s easier to just use Log in as root and enter setup to begin the If you can devote the whole drive to Minix, use
VirtualBox or Qemu to boot the ISO image – and at process. You’ll be prompted for your keyboard layout, the automatic mode. The files will be copied over, and
this menu, hit Enter to boot up Minix. and then move on to drive partitioning. then you can reboot into your new Minix installation.
www.linuxvoice.com 69
FOSSPICKS
Old school terminal emulator
Cool-retro-term
H
ollywood typically depicts bunch of extra packages. The
“hackers” as bespectacled interface is built around Qt 5.2, so
geeks sitting in front of you’ll need an up-to-date distro to
green text terminals with all sorts of build the source code – we used a
incomprehensible gobbledygook test release of Fedora 21. We
scrolling by. They’ll use these followed the instructions to the
cliches even in films set in the letter, but we still had to install
current decade, despite how daft some extras manually.
they are. But go back to the 70s and Anyway, once it’s running, it’s
80s and you would actually find pretty awesome. The developers
these flickery, eye-strain-inducing have done a great job of recreating
displays hooked up to mainframes an old-school text terminal, beyond
Top tip: enable this
and minicomputers. just making everything pixellated to simply didn’t work. It’s not clear
full-screen on your
If you want something today that the extreme. There’s a fuzziness whether this is due to a bug in the
laptop, go into a coffee
really harks back to the good old around the characters, irregularity shop, and watch as program or the mid-development
days of Unix, try Cool-retro-term. Its in the lighting, twitches from the everyone assumes status of Fedora 21, but we couldn’t
name says it all: it recreates an virtual CRT, and warping at the you’re the l33t3st h4x0r explore some of the extra features.
old-school terminal on your edges (simulating the bulge of a in the world. Still: you can normally customise
desktop, and it’s pretty cool. non-flat screen). Even if you never the font size and colour scheme,
Well, apart from compiling it. The used a Unix box in the 70s, it may and switch into a full-screen mode.
developers have provided a helpful still remind you of 8-bit computers
list of dependencies on the project’s hooked up to 80s TV sets. PROJECT WEBSITE
website, but if you’re not running Unfortunately, we couldn’t access https://github.com/Swordfish90/
cool-retro-term
KDE you’ll be pulling in a giant any of the settings; the menus
Screenshot taker
Maim
O
ne of the best command You can use the program straight
line tools for taking away by entering, for example,
screenshots is Scrot. With a maim foo.png to save the whole
command line tool you can take screen as foo.png. You’ll probably
batches of screenshots, selecting want to get the terminal window
specific areas, which is very handy out of the way first, though, so add
when you need to do repetitive jobs -d followed by a number to delay
(such as collecting images for the screenshot-taking process for
software documentation). Maim the specified number of seconds.
claims improve on Scrot with some If you want to grab a part of the
features that the former lacks. screen, you can specify coordinates
The main dependencies are using the -x, -y, -h and -w flags; in
Maim makes off-screen
Imlib2, libXrandr and libXfixes; many cases, though, you’ll want to areas transparent, extra settings. It’s also possible to
these are available as libimlib2-dev, select an area yourself. Maim can’t which is useful if you select a specific window using the
libxrandr-dev and libxfixes-dev on do this on its own, but if you install have multiple monitors -i flag. This requires the window ID,
Debian-based distributions. With Slop (linked to on the project’s with different which you can get by running
those in place, grab the latest website) then the -s flag lets you resolutions. xdotool selectwindow, clicking on
source code and build it like so: either click and drag to select an the window you want to capture,
git clone https://github.com/naelstrof/ area, or click on a window’s titlebar and noting the number. Enter maim
maim.git to take a screenshot of just that --help for the full list of options.
cd maim window. The selected window is
cmake ./ highlighted with a grey border, PROJECT WEBSITE
https://github.com/naelstrof/maim
make && sudo make install which you can customise using
70 www.linuxvoice.com
FOSSPICKS
Atari-like virtual machine
Aranym 0.9.16
T
here are many Atari ST/TT/ location of the file you downloaded
Falcon emulators doing the (eg /home/mike/etos512k.img)
rounds, and most of them and start Aranym again. All being
have very good compatibility with well, you’ll arrive at the desktop.
the original machines. Aranym (a From here, you can go about
contraction of “Atari running on any setting up your virtual Atari as you
machine”) is slightly different in that wish. You can reedit the
it doesn’t emulate a specific model configuration file to enable hard
from the ST series; it just emulates drives using disk images or
the best hardware suitable for an directories, and also tweak the
open source version of TOS, the video settings as well. Note that Aranym features JIT (just-in-time) translation for the emulated
ST’s old operating system. Aranym completely takes over your CPU, so it runs lightning fast.
After you’ve installed Aranym, mouse input when you’re using it,
you’ll also need to get a TOS image so if you need to get the cursor apps, and you can also enable
from http://emutos.sf.net. Like the back for other Linuxy work, press networking and get it online. Even if
original TOS, EmuTOS is a single- left Shift, left Control, left Alt and you didn’t have one of the machines
tasking operating system with Escape at the same time. at the time, it’s still great fun to play
certain limits, but it’s completely Aranym is compatible with many around with an OS that’s half a relic
open source and works really well original ST/Falcon games and of yesteryear, and half being kept
with Aranym. Fire up Aranym for the alive thanks to the passion of open
first time, and then close it; you’ll source hackers.
now have a file called .aranym/ “Aranym is a contraction of
config in your home directory. Edit
this to point the EmuTOS line to the
‘Atari running on any machine’.” PROJECT WEBSITE
http://aranym.sf.net
Text-mode Twitter client
Rainbowstream
A
command line Twitter let Rainbowstream read and post to
client may seem like a your feed.
crazy idea, but in most Back in the terminal, you can now
cases it works perfectly well. After begin using Twitter. Enter h to
all, tweets are really just plain text, display a list of help topics, which
and if you’ve ever spent much time you can then follow with another
with Mutt, WeeChat and similar word – for instance, h tweets will
tools, you’ll know that text-mode show you how to compose new
programs can be faster and more tweets. Entering home (optionally
efficient than their GUI equivalents. followed by a number) will show the
Rainbowstream is written in Python, most recent tweets on your
If you guessed this is a
so the quickest way to get it is: timeline, while mentions will show terminal, but it’s a lark nonetheless.
Raspberry Pi,
pip3 install rainbowstream tweets that mention you. It doesn’t congratulations – you Enter config to see a list of
The main dependency is Pillow, a take long to master, and if you can now apt-get remove configuration options for
fork of the Python Imaging Library. spend a lot of time on Twitter, you’ll your X server. Rainbowstream, and then enter:
Once you have it installed, enter appreciate its speed and efficiency. config IMAGE_ON_TERM=True
rainbowstream and your web Certain features aren’t enabled by Now, when you view the most
browser will pop up, prompting you default, such as the ability to display recent tweets from a user (eg view
to authenticate on Twitter. What’s inline images, as shown in our @linuxvoice), linked images will be
going on here? Well, Twitter doesn’t screenshot. This is really more of a displayed inline.
let random applications use your novelty than anything else, as the
images are inevitably low-resolution PROJECT WEBSITE
account, so first it performs a
www.rainbowstream.org
check, confirming that you want to given the constraints of the
www.linuxvoice.com 71
FOSSPICKS
Mail client
Alpine 2.11
W
e’ve given plenty of with patches. When you start Alpine,
kudos to the Mutt email you’ll note that it’s more welcoming
client in previous issues than Mutt, with a menu-driven
of Linux Voice, so some readers interface. However, like Mutt, there
have asked us to also give Alpine a are keyboard shortcuts for various
mention too. And for good reason options – these are displayed along
– it’s a great program, and this the bottom. If a shortcut looks like
author used it as his primary mail ^X, that means you have to press
client for much of the early 2000s. Ctrl+X to activate it.
To explain its history, however, we So, what makes Alpine great?
Alpine is easy and quick
need to take a deep breath: Alpine is Well, it’s very fast to use: once the configuration can be achieved
to set up, and doesn’t
a continuation of Pine, an email you’ve learnt the keybindings, you require extensive via the menus, so if you like the idea
client that started life in 1989 and can whizz around your mailboxes, hacking of config files. of a text-mode email client but don’t
was influenced by Elm (Electronic reading, replying to and sorting want to spend hours hand-crafting
Mail) before it. However, Alpine mails in a fraction of the time it configuration files, you’ll love this.
development ceased in 2008, and takes with the mouse. It’s also Alpine supports POP, IMAP and
since then users have made highly customisable, and you can SMTP servers out of the box, and
patches to add new features, along create colour themes for different can even browse NNTP groups. It
with a fork (re-Alpine). types of messages. Almost all of can render HTML emails, albeit
Are you following? In practical without much formatting, and
terms, it doesn’t really matter: if you supports several mailbox formats.
install Alpine from your distro’s “Alpine is a continuation of Pine, an
package repositories, you’ll almost
certainly get an updated version
email client that started life in 1989.” PROJECT WEBSITE
http://patches.freeiz.com/alpine
Source code analyser
PMD 5.2.0
E
veryone makes mistakes, Both tools are written in Java, so
especially when you’ve been extract pmd-bin-5.2.0.zip and
hacking away on the same jump into the pmd-bin-5.2.0/bin/
piece of code for several hours. You directory. You’ll need to provide a
may think you’re working well, but ruleset against which the code
niggling bugs could be creeping should be checked, along with a
into your code. If you’ve got a directory containing source code
deadline to reach and simply can’t files. For instance, if you want to
take a break, it’s worth running a check some JavaScript in
source code analyser on your work /var/www/foo, you’d use:
Here’s CPD in action,
before you ship it. ./run.sh pmd -R ecmascript-basic -d /var/ use something like this:
spotting repeating
PMD is one such analyser. It aims www/foo sections of PHP code. ./run.sh cpd --minimum-tokens 100 --files
to find flaws in your code such as Many other rulesets are available /var/www/foo --language php
unnecessary object creation, – see the project’s website for a full Ideally, this should help you to
unused variables, empty catch list. PMD will spit out its findings to reduce duplication, and stop bugs
blocks and other bloopers. stdout, or you can redirect them to from being repeated across other
Currently it only works with Java, another file by adding > list.txt to areas of the program. Plugins are
JavaScript, XML and XSL, but an the end of the command. available to integrate PMD and CPD
additional tool called CPD (the To run CPD, you need to specify with various IDEs, including Eclipse,
“copy-paste detector”) is provided, the language it should check, along NetBeans and JBuilder.
which identifies duplicated code in with a location and the minimum
PROJECT WEBSITE
more languages including C, C++, token length, which should be
http://pmd.sourceforge.net
C#, PHP and Ruby. reported as a duplicate. So you’d
72 www.linuxvoice.com
FOSSPICKS
FOSSPICKS Brain Relaxers
https://launchpad.net/pybik/
Flight simulator
FlightGear 3.2
H
ow many games can If you’re running an Ubuntu variant,
boast a 60,000 word there’s a PPA that has this latest
manual? Fortunately, FlightGear release
you don’t need to read it all to (ppa:saiarcot895/flightgear).
play FlightGear, but if you want to If you’ve ever tried a complex
get the most out of the simulator, flight sim before, you might’ve given
you’ll spend a lot of time with it. up before even getting off the
FlightGear is serious business: it ground, thanks to the sheer number
has been in development for of controls involved. FlightGear is no
nearly 20 years, it’s incredibly different, but at least with the
detailed, and it has realistic smaller aircraft like the Cessnas, “Hello, this is your captain speaking. We regret to announce
physics. Well, apart from the you can enjoy some simple flying some minor technical issues with this Ryanair flight to Málaga.
crashes... fun without burying your head in Normal service will be resumed soon.”
It’s also huge. You’re looking at the docs. Hit S to start your engine,
around 2GB for the complete hold 9 to ramp up the throttle, and the crashes aren’t very realistic
game, which includes over 30 when you’ve got some speed, tap 8 – you just bounce around on the
aircraft and hundreds of airports to lift off. Then use the 0 and Enter ground.) Still, if you manage to
around the world. Getting it is a keys to control the rudder. take off and land a 777, write in
bit difficult, as there’s no standard You won’t get far this way, as and let us know…
bundle for all Linux distros, so there are many more controls to
PROJECT WEBSITE
you’re left to your own distro’s master, but at least you’ll have a bit
www.flightgear.org
repositories or third-party repos. of fun before crashing. (And really,
Multi-dimensional Scrabble game
Scrabble3D
S
crabble, like most popular In its default mode, Scrabble3D
board games, has been lets you play a regular game with
done to death now. Sure, two, three or four players, dragging
it’s still a great game, but from the tiles from the top-right of the
squillions of computer versions window onto the board on the left.
we’ve seen over the years, there’s The game asks for your language
little to differentiate them. Until when you first start it, so that it can
we came across Scrabble3D, that download the relevant dictionary,
is. This adds another dimension and you can change this later on. If
to the proceedings, and thereby a you’ve got bored with the regular
whole other level to the Scrabble rules, some alternatives
gameplay. The program is written are available: Clabbers (which lets
using the Lazarus Pascal IDE, you place anagrams of words) and
Click Game > Run demo
which means that packages are Cambio Secco (whereby you can the slider under the 3D view on
to see the CPU play
available with both GTK and Qt exchange all of your tiles, once per against itself in the 3D the right to select a plane before
interfaces. The 64-bit Deb file match, without losing your turn). mode. dropping a tile. It’s a bit fiddly at
worked fine on our Ubuntu 13.10 To find the 3D mode, go into first, but the manual on the
test machine; if you’re running an Configuration > Settings, choose project’s site explains it well.
RPM-based distro such as Advanced mode, go to Board >
Fedora, you’ll also find suitable Configuration, and select 3D. After PROJECT WEBSITE
http://scrabble.sourceforge.net
packages at the project’s website. starting a new game, you can use
www.linuxvoice.com 73
LISTEN TO THE PODCAST
WWW.LINUXVOICE.COM
72
TUTORIALS INTRO
TUTORIALS
Dip your toe into a pool full of Linux knowledge with eight
tutorials lovingly crafted to expand your Linux consciousness
In this issue…
76 78 82
Ben Everard
is using technology as an excuse not to venture
out into the cold, dark world.
i3 RPi Input Markdown
I
t’s this time of year that technology Ditch your mouse and Les Pounder takes a There’s no need for fancy
seems most important to me. switch to a keyboard-driven Raspberry Pi, a PIR, an word processors: you
During the long days of summer, it desktop. Ben Everard has, ultrasonic distance sensor just need a text editor
sometimes feels like the solution to life’s and it’s made him more and a reed switch and and a bit of Markdown.
problems lies away from my desk and productive than ever. builds a biscuit protector. Marco Fioretti explains all.
outside in the fresh air. Then October
comes like a hard dose of reality with its
cold winds and rain, and by November
86 90 94
I’m ready to swear off nature for good
and retreat to the comforting glow of an
LCD screen. This time of year I like to
pick a project to see me through the
long nights until spring comes around
again and brings with it the desire to
step back out into the world.
This does, of course, beg the
Systemd Grub Atlas
question of what technology to focus It’s the most controversial Don’t wait until your Learn to program one of
on this winter (last year was Python program in Linux, but how bootloader breaks before the world’s first transistor-
and the Raspberry Pi – and launching a do you get it to work? you learn how it works. powered supercomputers
magazine of course). I haven’t quite Mike Saunders braves a Follow Mayank Shama’s with Juliet Kemp’s hands-
decided yet, but I think it might be time flamewar by investigating. guide today. on guide.
to get my Arduino out of its summer
storage and start putting it to use again.
Perhaps I should just buy a load of PROGRAMMING
components and start experimenting.
Hmm, does the cat needs an automatic Python Stdin and Stdout Battle robots
cat flap? Is the temperature in our 98 In part two of this series, 102 These two concepts are key 104 Are you the best
house monitored as accurately as it we delve deeper into the to all Unix-based systems, programmer around? Can
world of fractals. Depending on and you use them every time you you prove it? No, not by beating a
should be? Will this be the year I finally
your perspective these are either use Linux (even if you don’t know benchmark, but in the white-hot
get round to setting up a persistence of complex mathematical constructs you do); but how do we write heat of warfare! We introduce
vision system on my bike wheels? Oh, that reveal hidden truths about software that interacts with them? Robocode, programmable tank
there’s too much tech to play with, and nature, or pretty pictures. Either In this Code Ninja, we use Python warfare, and challenge you to see
not enough time. Why did I ever leave way, they’re a great way of to recreate a few classic who can write the most powerful
exploring programming concepts command line tools and learn tank. (No penguins were harmed
the house in summer?
with Python. about Stdin and Stdout as we go. in the writing of this article).
ben@linuxvoice.com
www.linuxvoice.com 75
TUTORIAL i3
i3: TILING WINDOW
TUTORIAL
MANAGEMENT
Forget about touchscreens for a moment, put the mouse down and
BEN EVERARD
control the desktop with your keyboard.
I
f you’ve always used a stacking window manager screen space, but this is just because you haven’t
WHY DO THIS?
(one in which windows overlap each other – most learned to use it well yet.
• Work more efficiently.
window managers are stacking), then the concept Once you’ve got used to the system, you should
• Keep carpal tunnel
of a tiling window manager may seem a little strange. find that you can do all your window management
syndrome at bay.
Using a tiling WM, you don’t have much control over tasks without your fingers ever leaving the keyboard.
• Get value for money
from your high- window placement, and there’s usually no taskbar for This is much faster than flicking back and forward
resolution monitor. minimised windows. Instead the whole thing is driven to the mouse. Don’t worry though, you won’t have to
by keyboard commands. At first, this can seem abandon your computer’s rodent – you’ll still be able
archaic. When you first use a tiling window manager, to use it for graphical applications. Now, let’s get stuck
you’ll probably find that it doesn’t make good use of in so you can see what it’s like for yourself.
Step by step: Get working with i3
1
Getting started 2
Windows and containers
You can install multiple window managers on a single Most of i3 is driven through a modifier key. This can
distro, so you can try i3 without losing your current be either Alt or the Windows key depending on the
setup. All you have to do is grab the package through setup (you may have been asked to choose when
your package manager (usually called i3). It’s available starting i3). The first thing we’ll do is open a terminal.
in all major distros. If you’re using Debian or Ubuntu This is done with Mod+Enter. Try with both Alt and
(or a derivative of these), you can adjust your Windows to see which way you have it set up.
repositories to get the latest version of i3 by following You’ll find that the terminal takes up the whole
the guide at https://i3wm.org/docs/repositories. screen, and that there are no window decorations
html; however, this isn’t necessary if you just want to for resizing, moving or closing it. That’s because i3
try it out. is a tiling window manager, and it handles all the
Once you’ve got everything installed, you just need placement and sizing.
to switch desktops. Log out of your current session To get an idea of how this works, press Mod+Enter
and you should be able to select i3 as an option on again. You should find that i3 opens another terminal
the login screen. This will take you into i3. You should either next to, or below the previous terminal.
see a desktop wallpaper with a black bar along the Whenever you open a new window in i3 it splits the
bottom. There’s no graphical menu (or anything else space of the current one to fit the new one in. If you
you might click with your mouse) as i3 is primarily press Mod+H before creating the new window, it will
keyboard-driven. If you’re used to doing most of your split the window horizontally, if you press Mod+V
work with the mouse, it may take a little while to get before, it will split vertically. This is the basic way of
used to this, but many people find that they end up organising your windows on the screen.
preferring a keyboard-driven interface.
76 www.linuxvoice.com
i3 TUTORIAL
3
Select the active window 4
Other applications
With multiple windows open on the screen, you can So far, we’ve only been playing with terminals. This is
use the mouse to select the one you want to use. useful to get a feel of how the desktop works, but it’s
However, this isn’t very efficient. It’s usually much not very good for general use (unless, of course, you’re
better to move around using the keyboard. You can a true Unix ninja). You can, of course, just start
move between the different panes (known as programs from terminals, but this means you have to
containers), either by using Mod+arrow key or by have terminals spewing out the output of the
using Mod+J, K, L or ; for left, down, up and right (the graphical programs.
same as in the Vi text editor). Although i3 doesn’t have a graphical applications
Once you’re in a container, you can use Mod+F menu, it does have a menu. To open it, press Mod+D,
to make it full-screen, or Mod+Shift+<num> (where then start typing the name of the program you want
<num> is a number) to send it to another workspace. to start. This works a little like tab completion in the
You can then go to the workspace by pressing command line. Unlike a desktop environment (such
Mod+<num>. If you do find yourself using the mouse, as Gnome or KDE), i3 doesn’t come with any specific
you can switch between workspaces by clicking on applications. All Linux software should work with i3,
the numbers in the bottom left-hand corner of the but it’s worth thinking about which applications fit
screen. One final use of the mouse is that you can use in best with the keyboard-driven way of working. For
it to resize containers by clicking and dragging the example, the Ranger terminal-based file manager can
border between them. be easier than a graphical tool like Nautilus or Dolphin.
5
More controls 6
Configuration
What we’ve covered so far needs to become second Since i3 is mostly aimed at advanced computer users,
nature to you, so now’s a good time to start practising. it’s highly customiseable. This is done through
Once you know all these key bindings automatically, modifying the config file ~/.i3/config or ~/.config/i3/
you should be able to use i3 for most work. However, config. In it, you should see that all the keybindings
there are still some more advanced features that can can be changed to whatever you want them to be. .
come in handy. As well as configuring i3, you can also get extra
Rather than tile a group of containers, you can software to help you. I3pystatus (https://github.
have them stacked or tabbed to give more screen com/enkore/i3pystatus) is a replacement for the
real-estate to the currently active container. You can status bar that’s extensible in Python. There’s also
switch between the various options with Mod+S, W or QuickSwitch (https://github.com/proxypoke/
E (for stacking, tabbed or default respectively). quickswitch-for-i3) which is a utility to help you find
You can also resize containers by using Mod+R and control windows in i3.
to enter resize mode. Once you’ve pressed that, you If you get stuck, i3 has good documentation at
should see Resize Mode appear in the bottom-left http://i3wm.org/docs/. There’s also a stackoverflow-
corner. You can then use the arrow keys or J, K, L and style FAQ at https://faq.i3wm.org/questions which
; (without Mod) to resize the current container. Once is a good place to find solutions since most problems
you’ve finished, press Escape to exit resize mode. you face will have happened to someone before.
www.linuxvoice.com 77
TUTORIAL RASPBERRY PI
RASPBERRY PI:
TUTORIAL
SIMPLE FORMS OF INPUT
It's time to play with some affordable methods of getting input into
LES POUNDER
your tiny Linux machine.
W
hen thinking input methods for a computer
WHY DO THIS?
we generally think of keyboards and mice,
• Create a multi-sensor but there are many other different types of
alarm system to protect
coffee and biscuits. input. For example, the use of touch and gesture
• We will program it using controls in mobile devices is thanks to capacitive
Python and build a user touchscreens and accelerometers feeding data to the
interface using a module system that acts on the input. Sensors are unique
called easyGUI.
forms of input. They provide information about the
• Learn about sensors
and alternative methods world around us and can be used to trigger alarms,
of input. gather data on animals and provide valuable data for
scientific research.
In this tutorial we will look at two sensors and a Our final project is ready to defend against the hordes of
TOOLS REQUIRED
magnetic switch, all of which are really simple forms digestive eating enemies or hungry dogs.
• Raspberry Pi (Any
model). of input. For our sensors, we have an ultrasonic
• Raspbian OS. sensor commonly used to sense distance and found enables Python to use the GPIO pins. It's called RPi.
• PIR sensor (BISS00001 in cars' parking sensors. We will then use a sensor GPIO, but this is rather unwieldy to use in our code so
are very common on commonly used in burglar alarms to detect we rename it to GPIO instead:
eBay). movement – this is a Passive Infrared (PIR) sensor. import RPi.GPIO as GPIO
• HC-SR04 Ultrasonic Our magnetic switch is called a reed switch, and these import time
Sensor (Less than £5 on
eBay). are commonly used as door sensors. Next we set up the GPIO to use the logical BOARD
• Reed Switch (We used pin numbering system and then create a variable
http://uk.farnell.com/ PIR sensor called PIR_PIN to contain the real GPIO pin that we
comus/8601-0211-015/ Passive Infrared sensors operate by monitoring will use as an input for the trigger. The last line
switch-reed-spst-
no-0-1a-24v-smd/ infrared light. When it detects movement, the sensor instructs Python that we are using pin 7 as an input
dp/2409191) sends a high signal to your Raspberry Pi, which we and that it should expect to receive a trigger:
• Male to male jumpers. have programmed to react. GPIO.setmode(GPIO.BOARD)
• Male to female jumpers. PIR sensors are one of the easiest sensors to wire PIR_PIN = 7
• 1kΩ resistor. up to your Raspberry Pi, as they only come with three GPIO.setup(PIR_PIN, GPIO.IN)
• Breadboard. connections: VCC, which connects to the 5V pin of Now we have a little fun and print some funny
your GPIO (pin 2); GND or ground, which connects to system messages to the console:
pin 6; and finally Output (the pin that sends the alert print("Welcome to the LV Biscuit Barrier - System Loading
signal to our Pi), which connects to pin 7 of your Pi. Please Wait")
With the sensors connected, let's build the Python
code that will enable us to use it.
Installing EasyGUI
Using the PIR sensor with Python is relatively
straightforward, requiring nothing more than telling We’ve covered EasyGUI in previous issues of Linux Voice. It
the Raspberry Pi which GPIO pin the PIR sensor is is the simplest method of creating a user interface, and can
be inserted into existing code with relative ease.
attached to and to watch the status of that pin for any
There are two ways to install EasyGUI: via your package
changes. We start by importing two modules: the first manager and via a special Python package manager.
First of all let us use the Raspbian package manager,
which is called apt.
To install EasyGUI open a terminal and type in the code
below followed by the enter key
sudo apt-get install python-easygui
We can also use a Python package manager called PIP to
install the packages and keep them up to date. But first we
We used ultrasonic
need to install PIP using the apt command.
sensors to detect distance
In a terminal window type
to the biscuit – they also sudo apt-get install python-pip
make a great pair of eyes sudo pip install easygui
for a robot.
78 www.linuxvoice.com
RASPBERRY PI TUTORIAL
time.sleep(2) Resistors
print("Scanning for intruders") Resistors are an essential part of electronics, components would have a shorter life span
The last segment of code is the loop that and are used to reduce the electrical current and we could damage our Raspberry Pi.
continually looks for a trigger on the PIR_PIN. Once flow and in turn reduce the voltage passing Resistors come in a series of colours meant
someone tries to steal a biscuit they trigger the trap through a circuit. A simple example of to identify their resistance value, measured
the use of resistors is the humble Light in Ohms (Ω). Common resistors used with
and a message is printed to the console informing us
Emitting Diode (LED). They work with the the Raspberry Pi are
of the situation. With the alarm triggered, the system 3.3V voltages used on the Raspberry Pi but 220Ω = red, red, brown, gold
waits for 1 second before resetting and waiting for its run hot and bright, just like Rutger Hauer in 1kΩ = brown, black, red, gold
next incursion: Blade Runner. Using a resistor inline with 10kΩ = brown, black, orange, gold
while True: the power from the Raspberry Pi pin we can If you would like to know more about
reduce the current and voltage, extending resistors, there is a great Wikipedia article
if GPIO.input(PIR_PIN):
the life of our LED. Without resistors, http://en.wikipedia.org/wiki/Resistor.
print("Motion Detected near the biscuits")
time.sleep(1)
ready to receive the alarm trigger:
Reed switch reed = 26
A reed switch is a small glass tube containing two GPIO.setup(PIR_PIN, GPIO.IN)
strips of metal separated by about 1–2mm of space GPIO.setup(reed, GPIO.IN)
but overlapping. The switch has a “normally open” There are no changes made to our system starting/
position, but when a magnet is introduced the two greeting message:
strips of metal snap together and complete a circuit print("Welcome to the LV Biscuit Barrier - System Loading
thus allowing the current to flow through the switch. Please Wait")
Remove the magnet and the switch opens, breaking time.sleep(2)
the circuit and stopping the current flowing. print("Scanning for intruders")
Wiring up a reed switch is extremely simple, and is Here we see the most significant addition to our
very breadboard friendly. Connect the 3V3 pin from code – we create a second condition, that of the reed
your Raspberry Pi to one end of the reed switch using switch being triggered. If this condition is true then the
a breadboard – either end of the switch can be used. code will print the word “Trigger” in the console:
The other end of the switch connects to pin 26 on while True:
your Raspberry Pi via the breadboard. if GPIO.input(PIR_PIN) == True:
Using a reed switch with Python is just as print("Motion Detected near the biscuits")
straightforward as the PIR sensor, and we will reuse time.sleep(1)
some of the same code. Let's take a look at the elif GPIO.input(reed) == True:
additions made for the reed switch. print("Biscuit tin has been opened CODE RED!!!")
The first part of the code remains the same: time.sleep(1)
import RPi.GPIO as GPIO
import time Ultrasonic sensors
GPIO.setmode(GPIO.BOARD) Ultrasonic sensors have two 'eyes' – one is a trigger
PIR_PIN = 7 that sends a pulse of ultrasound towards an object,
In a similar way to the PIR_PIN variable, we use which then bounces off the object and returns to the
another variable to store the GPIO pin used for the other eye which is called echo. The distance is
input, which is then configured to be an input pin measured using a simple calculation:
Distance = Speed * Time
The most common ultrasonic sensor is the
HC-SR04, which can be found for a few pounds on
eBay. They come with 4 pins:
VCC 5V power from your Raspberry Pi (Pin 1).
GND Ground (Pin 6).
Trigger Receives a signal from the Raspberry Pi to
send a pulse of ultrasonic sound (Pin 11).
Echo Receives the reflected ultrasonic pulse and
sends a signal back to your Raspberry Pi (Pin 13).
Because we are working with 5V power we need to
protect the GPIO pins of our Raspberry Pi, as they can
only work with 3.3V or less. To do this we use a
resistor to reduce the voltage down to something
more Pi friendly. We’ll use a 1kΩ resistor which has a
colour code of BROWN, BLACK, RED, GOLD.
A reed switch is an open switch inside a glass vial – when To enable the ultrasonic sensor to work with our
a magnet is introduced the switch closes. existing Python code we need to make quite a few
www.linuxvoice.com 79
TUTORIAL RASPBERRY PI
Our next line is a conditional statement that checks
PIR sensor
HC-SR04 ultrasonic to see if the sensor is detecting anything, if not then
sensor
the code continues. To enable the sensor to 'settle' we
introduce a delay using time.sleep of 0.3 seconds.
3V power ONLY to
reed switch
The next line instructs our Raspberry Pi to send an
ultrasonic pulse, via sending a high signal to the
trigger pin of our ultrasonic sensor. We then delay for
Reed switch 10 microseconds, which is just enough time for a
pulse of significant length to be sent. Then we turn off
the trigger pin and flow into two while statements.
While the echo pin is not receiving an ultrasonic
Ground to – rail
pulse it updates the variable signaloff with the current
time, and a similar construction is used for signalon
5V Power to – rail
when we receive the ultrasonic echo pulse.
With the two times recorded we now do a little
maths. Subtracting the signaloff time from signalon
time gives us the time taken for the pulse to be sent
and return to the ultrasonic sensor, and this is saved
as the variable timepassed:
def reading(sensor):
global distance
if sensor == 0:
time.sleep(0.3)
Here's how the circuit is
changes. The imports remain the same as in previous GPIO.output(trigger, True)
built – a larger version is
available in the project’s sections, but you will notice two new variables called time.sleep(0.00001)
GitHub repository, see box trigger and echo. These new variables identify the GPIO.output(trigger, False)
for details. GPIO pins used to send (trigger) and pulse from the while GPIO.input(echo) == 0:
ultrasonic sensor and receive (echo) an ultrasonic signaloff = time.time()
pulse. On the last line you will see something called while GPIO.input(echo) == 1:
global distance. This is a variable available outside signalon = time.time()
and inside of a function and, without adding the global timepassed = signalon - signaloff
element, we would not be able to use the variable Now we perform another calculation, using the
inside of a function that we create later in the code: school equation distance = time * speed. Our
import RPi.GPIO as GPIO distance variable stores the answer to the time
import time passed multiplied by 17,000 (the speed of sound) for
GPIO.setmode(GPIO.BOARD) a half second, so a full second is 34,029 centimetres
PIR_PIN = 7 travelled. Why a half second? Well, we halve the time
reed = 26 taken as we need to know the distance from the
trigger = 11 object, not the time taken to get there and get back.
echo = 13 We then print the distance in the console. Our last line
global distance in the function is the end of the if..else conditional
Next we configure the pins used for the ultrasonic logic and is used to capture any errors:
sensor: trigger is an output and echo an input. We distance = timepassed * 17000
also instruct the trigger GPIO pin to be “Low” (in other return distance
words start the program with no power being sent to else:
that pin), to reduce the chance of a false reading: print "Error."
GPIO.setup(PIR_PIN, GPIO.IN) Now we're on to the home straight and back to the
GPIO.setup(reed, GPIO.IN) main loop of our code. We keep the first two sensors,
GPIO.setup(trigger, GPIO.OUT) our PIR_PIN and reed the same, and we introduce
GPIO.setup(echo, GPIO.IN) another elif statement that checks to see if the
GPIO.output(trigger, GPIO.LOW) variable distance is less than 10cm. If so, it prints
We keep the system startup message the same: “Biscuit Thief” in the console:
print("Welcome to the LV Biscuit Barrier - System Loading while True:
Please Wait") reading(0)
time.sleep(2) if GPIO.input(PIR_PIN) == True:
print("Scanning for intruders") print("Motion Detected near the biscuits")
Next we create a function called reading that time.sleep(1)
controls the use of the ultrasonic sensor. We reuse the elif GPIO.input(reed) == True:
global distance variable, thus linking the variable and print("Biscuit tin has been opened CODE RED!!!")
enabling it to be used in our code. time.sleep(1)
80 www.linuxvoice.com
RASPBERRY PI TUTORIAL
elif distance < 10:
print("Biscuit thief has struck again, deploy
ill-tempered jack russell terrier")
So far our code is just outputting the responses to the
console which is good but not great. So how can we
make our project great? A great user interface will help
users to quickly use the project.
So where do we need a user interface in our
project? First of all a cool splash page that shows off
the Linux Voice logo and what the project is all about.
After that we need three dialog boxes, one for each of
the inputs, that will respond to any of the triggers that
may occur when our biscuit thief strikes. Version 2 uses EasyGUI
Line 74 to create a simple user
Coding our splash screen else: interface that's a lot
Using EasyGUI we need to replace the system starting print("EXIT")
friendlier to use.
text with a custom splash screen. To do that we need Next we create three dialog boxes that will handle
to create a folder called Images and download the the reporting of incursions in our project. Our three
Linux Voice logo (these files are included in the project triggers are a PIR sensor, a reed switch and an
files from GitHub). So in our code we first need to add ultrasonic sensor, and we created three conditions in
one more variable in the form of: our code that look like this:
logo = "./Images/masthead.gif" #First condition this handles the PIR sensor being tripped
And a list that contains the possible responses to a if GPIO.input(PIR_PIN) == True:
simple yes, no question. print("Motion Detected near the biscuits")
activate = ["Yes","No"] time.sleep(1)
With those additions made, our focus turns to the #Second condition handles the reed switch being triggered by
welcome message that we earlier coded: our magnetic biscuit tin lid
print("Welcome to the LV Biscuit Barrier - System Loading elif GPIO.input(reed) == True:
Please Wait") print("Biscuit tin has been opened CODE RED!!!")
time.sleep(2) time.sleep(1)
print("Scanning for intruders") #Our third and final condition uses the output from the ultra()
We can replace it with: function to tell us if the thief's hand is less than 10 cm away
splash_title = "Linux Voice Biscuit Security System V2" elif distance < 10:
splash_msg = "Would you like to protect the biscuits?" print("Biscuit thief has struck again, deploy ill
start = buttonbox(title=splash_title,image=logo,msg=splash_ tempered jack russell terrier")
msg,choices=activate) For each we used a simple print function to handle
So we have a title in the form of the variable the reporting, but instead of this let's use a GUI dialog
splash_title for our dialog box, and a question for our box. So for:
users in the form of splash_msg. The potential print("Motion Detected near the biscuits")
answers are stored in the list activate and this answer print("Biscuit tin has been opened CODE RED!!!")
is saved as a variable start, which we will use in the print("Biscuit thief has struck again, deploy ill tempered jack
next piece of code. russell terrier")
Our focus now shifts to line 58 of the code, which is Replace with:
the start of an if...else statement. We use the answer msgbox(title="Motion Detected", msg="--ALERT-- I have
to the splash question to drive the activation of the detected movement")
project. If the user answers yes, then the main body of msgbox(title="Biscuit tin has been opened CODE RED!!!",
code is run; else if the user answers no, then the msg="--ALERT-- I have detected that the tin has been opened")
program exits: msgbox(title="Hand in the biscuit tin", msg="--ALERT-- Biscuit
Line 58 thief has struck again, deploy ill tempered jack russell terrier")
if start == "Yes": We can see that the msgbox function has a simple
… syntax, and that it needs a title for the dialog box and a
message to report to the user.
We have learnt how three different types of input
Where can I find the completed code?
work, how they are wired up to our Raspberry Pi and
I've made the code for this project publicly available via how we can create a Python program that will enable
Github. For those that are familiar with Github you can us to track down our biscuit thief. Yum!
clone the repository at https://github.com/lesp/LinuxVoice_
Biscuit_Security or for those unfamiliar you can download
Les Pounder is a maker and hacker specialising in the
the archive as a zip file from https://github.com/lesp/
Raspberry Pi and Arduino. Les travels the UK training
LinuxVoice_Biscuit_Security/archive/master.zip teachers in the new computing curriculum and Raspberry Pi.
www.linuxvoice.com 81
TUTORIAL MARKDOWN
MARKDOWN: WRITE ONCE,
TUTORIAL
PUBLISH ANYWHERE
Stop wasting time with word processors and follow the Markdown
MARCO FIORETTI
way to future-proof your words.
M
arkdown is just one of many plain text content, automating as much as possible of the work.
WHY DO THIS? markup systems available as Free Software To really understand how and why Markdown is great,
• We produce more and (we’ll return to that definition in a moment). we have to remember the implications of the current
more text every year, Writing in Markdown is simple enough to understand, “What You See is What You Get” (WYSIWYG)
and never know how it but the real challenge behind Markdown is in paradigm. In order to give you WYSIWYG, modern
will be reused.
understanding why it was created, why it can be good word processors automatically add tons of data and
• Even Free Software can
become obsolete, but a for you, and above all, how to change your writing and instructions to all the files they save in their native
source format as simple publishing habits in order to get the greatest formats, and these instructions often aren’t all that
as Markdown will always advantage from it. portable between formats. The result is more things
remain usable.
If you don’t regularly create significant amounts of that could go wrong whenever something changes,
• If you produce lots of
text, your productivity text of whatever nature, from poetry to company or more temptation to make things look “just right”
will increase. Trust us. parish newsletters, Markdown will be of little or no manually, and more work to move from one format to
relevance for you. But if you do, or even if you just edit, the other, eg from OpenDocument to HTML or PDF.
manage and publish texts written by others,
Markdown can be a real blessing, for two big reasons. Separate style and substance
The first Markdown goal is to separate content A plain text file, instead, is a file that contains only the
from formatting as much as possible, to save time bytes corresponding to the actual letters, punctuation
and concentration. After decades of word processing, and typographic “operators” – that is spaces, tabs and
and seeing too many “professionally formatted” texts newlines – that we type into it using a text editor.
looking horrible on the Web or in our smartphones, we Such files sure don’t look as pretty on screen as the
have all learned that all too often, many of the pages of commercial magazines, but we should learn
functions in traditional office suites produce just a big not to care. They are extremely portable and,
waste of time and energy. We obsess ourselves with consequently, much more future-proof than any other
fonts, margins and similar formatting details instead alternative. They also avoid distractions: the less eye
of just writing clearly. Then, much of that effort goes candy you can add or see, the more you are forced to
down the drain every time somebody loads what we ask yourself if what you wrote IS worth reading.
You never know when
wrote into another program, or on a small screen. Very often, however, the deliberate limitations of
you will need to republish
something you wrote – so The second, even bigger rationale for Markdown plain text files may hurt the clarity and readability of
why not use a multi-output may be summarised with the slogan “Write once, your writing. Structures and properties like
source format right from publish anywhere”. In other words, the simpler your indentation, lists, typefaces or embedded images do
the beginning? initial format is, the easier it will be to reuse your make text easier to understand, don’t they? The
solution is to express them by marking the text up by
adding normal characters with a special meaning,
called markers or, more frequently, tags. Let’s take the
italic typeface as an example – a markup user would
never apply it by selecting text and then clicking on
some “italic” button, or menu entry. They would,
instead, adopt a convention like “//all text between a
couple of slashes is meant to be italic//” and then just
type (and see on screen or paper!) those extra
characters, every time italic is needed. Primitive and
ugly? Maybe, but also extremely efficient.
Markdown, finally
After this long, but absolutely necessary introduction,
we can finally define what Markdown is, and how to
use it. First, it’s a set of rules to mark up plain text,
defined by John Gruber in 2004. See the “Flash
introduction to Markdown syntax” box for some
82 www.linuxvoice.com
MARKDOWN TUTORIAL
examples. Second, it’s the software that converts that
text to whatever target format its users need in any
given moment. Write
The basic Markdown syntax, and all the programs
written for it, were conceived for the web, to define
and generate basic HTML. Very soon after the
appearance of Markdown, however, other developers
created syntax extensions and corresponding
applications to make it possible to convert Markdown
into ODF, Latex and more. Let’s look at the basics first, Convert
however. No problem!
Markdown was designed to satisfy two non-
negotiable criteria; efficiency and, above all, readability.
If you ask your browser to show you the source of any
web page, you will immediately remember that the “M”
Need another Publish
in HTML means just that: “Markup”. The problem is STOP format?
that writing and reading raw HTML markup is tiring,
error-prone and time consuming. By contrast, the
main rule in Markdown is that any text formatted with
it should be easily readable as-is, even by people who
This is the power of the
have never even heard of Markdown. As many long block of HTML that corresponds to one object
Markdown flow: once
advocates of this method say “the single biggest (eg a table, or one preformatted chunk of source you have written the
source of inspiration for Markdown’s syntax is the code), and as such is enclosed by a matching pair of source, you can repeat the
format of plain text email”. tags, like <table> and </table>. Inside .md files, such conversion and publishing
To favour readability, all Markdown tags consist of elements must be preceded and followed by blank steps as many times you
punctuation characters, chosen to look as unintrusive lines, and their enclosing tags cannot be indented with want.
as possible. The idea is to write Web-ready content tabs or spaces.
faster, not to insert HTML tags faster. By deliberate
choice, tags are defined only for that very small The Markdown flow
subset of HTML that corresponds to properties or In the real world, a complete Markdown-based
operations applicable to raw text. For any other publishing flow will have at least these three phases:
markup, from page backgrounds to navigation menus, 1 Generate your text with all the required Markdown
you are supposed to use HTML (In practice, as we will tags. PRO TIP
see shortly, there are ways to not perform such 2 Run the converter that generates the HTML version
Even if you decide to not
operations manually in many cases). (or other formats, if needed) of your work. use Pandoc to generate
In a Markdown file (the standard extension is .md) 3 “Publish” that version, that is send it by email to the output formats
of your Markdown
you can switch from Markdown to full HTML and back whoever may need it, put it online and so on. documents, study and try
at any moment, without problems. The only restriction Can you see the efficiency, power and flexibility, in it a few times. If nothing
is for block-level elements – that is, practically every one word: the freedom embedded in a flow like this? else, it may help you to
convert all your text files
No? Don’t worry, here it is: there is no need to perform to Markdown, even if
those operations all on the same computer, all by the they are in Microsoft or
Documentation same person, or manually, or all at once. As far as OpenDocument formats.
phase 1 is concerned, any text editor, on any operating
Cheatsheets? Yes, a good, detailed cheatsheet is all you
will need to get started with Markdown after reading this system, can be used to write Markdown (or to update
tutorial. Don’t ask us for one, however. Search for them Markdown files that somebody else wrote 10 years
online and you’ll find plenty, in all possible formats from ago). And if you’re using a halfway decent editor, it will
Markdown (of course!) to desktop wallpapers. Once you surely have a Markdown syntax highlighting mode. If
have learned Markdown, study the practical YAML tutorial
you wanted to publish the log files from your server,
at http://rhnh.net/2011/01/31/yaml-tutorial.
Before that, however, we suggest you read the post your email archive or any other body of plain text, you
www.terminally-incoherent.com/blog/2012/05/25/ could write a script that converts everything to
Markdown-for-muggles, which is a funny encouragement Markdown, and make the whole flow automatic.
to use Markdown. Another article to read before starting Phases 2 and 3 can be very easily delegated to a
is ‘Thoughts on Markdown’ (www.leancrew.com/all-
cron job, and often should be. There is also no
this/2010/10/thoughts-on-markdown). On a more technical
level, other useful resources are the man page ‘pandoc_ problem if years pass between one phase and the
markdown’, which explains the differences between basic next. Everything you produce with a system like
Markdown and its Pandoc superset, and the lists at Markdown is, by definition, reusable in ways that you
https://github.com/jgm/pandoc/wiki/Pandoc-vs- may not even know that you’ll need one day. For
Multimarkdown. That wiki page thoroughly compares the
example, suppose next year some blog invites you to
two extended converters feature by feature, starting with
the input and output formats they support. republish stuff you wrote in 2008. If that stuff is in
Markdown format, and the webmaster is willing to
www.linuxvoice.com 83
TUTORIAL MARKDOWN
install the Markdown QuickTags plugin for WordPress,
all you’ll need to do is copy and paste your Markdown
sources in the WordPress form. Please stand back one
moment in silence with us, to appreciate the
awesomeness of it all!
A practical example
Here’s a simple Markdown source file snippet that
PRO TIP mixes both HTML code (in this case for a navigation
Whatever Markdown menu, not the actual content!) and Markdown:
converter you choose, you
shouldn’t use it directly at <!-- Navigational markup -->
the prompt. Instead, write <ul class=”nav”>
a shell script that will call <li<a href=”./”>Home</a></li>
it automatically and save
a log file somewhere. This <li><a href=”contact/”>About</a></li>
will greatly reduce the <li><a href=”contact/”>Contact</a></li>
possibility of mistakes, </ul> This is what the Markdown syntax looks like in a text
and make you work even
faster. editor. Marked text is coloured to make it even more
“...MultiMarkdown provides an easy way to share formatting readable, while embedded HTML code is left as is.
between all of my devices. It’s easy to learn (even for us mortals)
and immediately useful.” title. The problem, of course, is that this will generate
> --- David Sparks, [MacSparky.com](http://MacSparky.com/) enough HTML to display your image, but not enough
to align, frame and size it just as you wish. There are
## Why Markdown and MultiMarkdown? two solutions here. One is to not use Markdown for
Because life is too short to waste it *formatting* text, instead of images, but actual HTML, with all the options you may
just **writing it**. need:
The image below shows the full HTML version <img src=”/path/to/img.jpg” width=”95%” alt=”Here you should
generated by any Markdown converter, and the image see an image”
on the facing page shows the way it looks inside a A much smarter way to go is to write plain
web browser. See what we meant? Even without Markdown, and then pre-process your sources with
detailed explanations, or having a cheatsheet handy, an extra script that replaces all the Markdown image
both the original plain text and what is eventually tags with equivalent ones in HTML, all with the same
shown by a browser are much more readable than the settings, CSS classes and so on.
HTML. As far as hyperlinks are concerned, the syntax itself
is very simple:
Images and hyperlinks This is [an example](http://example.com/ “Title”) inline link.
One image is worth a thousand words, or so they say, This is [an example][id] reference-style link.
but how do we handle them in plain text files? The The first line shows how to define links to a generic
answer is “With a little bit of care”. You can tell your web page: you put the URL inline between the string
your Markdown converter to insert in the target file the that will become clickable text (the part in square
HTML code that displays an image using this syntax: brackets) and the title that will appear when a user
 links are much more interesting, at least for frequently
converting the Markdown This combines three strings: alternative text for used URLs. The second square bracket is a pointer to
source of our snippet. textual browsers, a path to the image, and the image the complete definition of the URL that goes there,
which will have this format:
[id]: http://example.com/ “Optional Title Here”
and can be anywhere in the Markdown file! This
means that you can write your own list of frequently
used URL aliases, all in one file, and then append it
with a script to all the Markdown sources that need
any of those URLs!
Templates and metadata with YAML
Markdown is good, and powerful. Adding metadata to
it makes it much more powerful. How? A very
common way to do it is by using YAML (which is
another of those annoying recursive acronyms – this
one stands for “YAML Ain’t Markup Language”). This is
an open standard, designed to store generic,
structured textual data just like XML, but in a way
84 www.linuxvoice.com
MARKDOWN TUTORIAL
that’s much more easily readable and editable by
humans. YAML metadata is usually placed in a
separate frontmatter, at the very beginning of a
Markdown file, between two lines containing three
dashes each:
Title: My first Markdown/YAML post
date : 2014-08-01
categories: Free Software, Blogging, Open Standards
Please note that this is a very trivial example of
YAML. As simple as it looks, YAML can store many
types of data, from lists and abstracts to associative
arrays. There are plenty of free Software parsers that
can process it, or generate YAML frontmatter from
many sources. Used together, YAML and Markdown
can handle large amounts of text in a way that is very
easy to use, but also very powerful.
Markdown editors and converters
As we already said, any halfway decent editor will
The final result: fully
make your Markdown source files even more formats supported, and in the set of Markdown tags standard code that any
readable, thanks to syntax highlighting. When it they recognise and can process. Therefore, there is no browser will render without
comes to conversion, there are many choices. You “best converter”. You must figure out by yourself problems, with a structure
can even generate HTML from Markdown sources which one best matches your taste or, more perfectly matching the
when working on somebody else’s computer, by using importantly, the type of documents you must write. original Markdown file.
the official online tool, called Dingus (https:// The original converter, for example, only accepts basic
daringfireball.net/projects/markdown/dingus) or one Markdown and outputs HTML. Pandoc, instead, is a
called Dillinger (http://dillinger.io), which you can even generic tool that can also be used to convert to the
install on your own server. Markdown format Web pages or many other
On a Linux desktop, you can use the original documents.
converter, a Perl script called markdown.pl, or more Pandoc defines extra Markdown tags to handle,
advanced tools like Pandoc (http://johnmacfarlane. among other things footnotes, tables, flexible ordered
net/pandoc) or Multiple Markdown (MMD, http:// lists, automatic tables of contents, embedded Latex
fletcherpenney.net/multimarkdown). They are all formulas, citations, and markdown inside HTML block PRO TIP
command line tools, well suited for automation, and elements. When you run the converter, multiple input Markdown is great and
relatively simple to use. Basically, you pass them the files are concatenated automatically. Pandoc can may be a good reason
input file (or the Standard Input) and the name of the even accept URLs as input files! Output goes to to change text editor,
if your favourite one
output file in which they should save the result. The stdout by default, except for complex formats like doesn’t highlight its tags
differences are in the number of input and output OpenDocument or ePUB. In this way, it’s also possible properly. We suggest you
to generate PDF files directly from Markdown. try multiplatform editors
if you haven’t already, as
The other most useful features of Pandoc are the
Flash introduction to Markdown syntax they allow you always to
command line options that tell it to place the content work in the same way!
Warning! This is very far from being a complete description of external files, for example SEO keywords, in the
of the Markdown syntax. We only want to whet your
header of the HTML output, or at the end of a page.
appetite by showing how easy it is to create structured, yet
highly readable plain text using Markdown. Besides, even MMD is another pair of Markdown syntax superset
if we had enough space, it would make no sense to give and associated converter. It is optimised for handling,
you a complete syntax primer here. The whole format is so among other things, tables, footnotes, citations,
simple, and already completely documented in countless internal cross-references and equations. Cross-
cheatsheets that it would make no sense to copy it here:
references, for example, work in this way:
*Single asterisks (or underscores) enclose italic text*
**Couple of asterisks, instead, mean “bold!”** [This string will point to an internal link][mylink]
Headers can be marked in two ways. The simplest is this: ## This is where I will end up when clicking on the string above
# Level 1 header # [mylink]
## Level 2 header ## MMD can also convert Markdown sources to Latex,
Numbered lists:
which is the basis for professional-quality PDFs, with
1. Foo
2. Bar its auxiliary tool mmd2tex. Other, extremely important
Unordered lists: output formats supported by MMD are
* first list item OpenDocument and OPML, the standard used in the
* another list item Fargo 2 blogging platform.
> Block quotes work just like in email.
> Put a “>” sign at the beginning of
Marco Fioretti is a Free Software and open data campaigner
> each of their lines. who has advocated FOSS all over the world.
www.linuxvoice.com 85
TUTORIAL SYSTEM SERVICES
LINUX 101: GET THE MOST
TUTORIAL
OUT OF SYSTEMD
It’s mightily controversial – but Systemd is here to stay.
MIKE SAUNDERS
Learn how to use its features, and (maybe) learn to love it too…
H
ate mail, personal insults, death threats – at specified intervals, and much more. It’s growing all
WHY DO THIS? Lennart Poettering, the author of Systemd, is the time, and becoming something of a “base system”
• Understand the big used to receiving these. The Red Hat for Linux – providing all the plumbing tools needed to
changes in modern employee recently ranted on Google+ about the boot and maintain a distro.
distros. nature of the FOSS community (http://tinyurl.com/ Now, Systemd is controversial for various reasons:
• See how Systemd poorlennart), lamenting that it’s “quite a sick place to it eschews some established Unix conventions, such
replaces SysVinit.
be in”. In particular, he points to Linus Torvalds’s highly as plain text log files. It’s seen as a “monolithic” project
• Get to grips with units
and the new journal. acerbic mailing list posts, and accuses the kernel trying to take over everything else. And it’s a major
head honcho of setting the tone of online discussion, change to the underpinnings of our OS. Yet almost
making personal attacks and derogatory comments every major distribution has adopted it (or is about
the norm. to), so it’s here to stay. And there are benefits: faster
But why has Poettering received so much hate? booting, easier management of services that depend
Why does a man who simply develops open source on one another, and powerful and secure logging
software have to tolerate this amount of anger? Well, facilities too.
the answer lies in the importance of his software. So in this tutorial we’ll explore Systemd’s features,
Systemd is the first thing launched by the Linux kernel and show you how to get the most out of them. Even
on most distributions now, and it serves many roles. It if you’re not a fan of the software right now, hopefully
starts system services, handles logins, executes tasks at least you’ll feel more comfortable with it by the end.
1 BOOTING AND SERVICES
This tongue-in-cheek
animation at http://tinyurl.
Almost every major distro has either adopted should be the same regardless of your distro. That’s
com/m2e7mv8 portrays
Systemd as a rabid animal Systemd, or will do so in the next release (Debian and one of the plus points of Systemd: it obviates many of
eating everything in its Ubuntu). In this tutorial we’re using a pre-release of the tiny, niggling differences between distros.
path. Most critics haven’t Fedora 21 – a distro that has been a great testing In a terminal, enter ps ax | grep systemd and look at
been so fluffy. ground for Systemd – but the commands and notes the first line. The 1 means that it’s process ID 1, ie the
first thing launched by the Linux kernel. So, once the
kernel has done its work detecting hardware and
organising memory, it launches the /usr/lib/systemd/
systemd executable, which then launches other
programs in turn. (In pre-Systemd days, the kernel
would launch /sbin/init, which would then launch
various other essential boot scripts, in a system
known as SysVinit.)
Taking control
Central to Systemd is the concept of units. These are
configuration files with information about services
(programs running in the background), devices, mount
points, timers and other aspects of the operating
system. One of Systemd’s goals is to ease and
simplify the interaction between these, so if you have
a certain program that needs to start when a certain
mount point is created when a certain device gets
plugged in, it should be considerably easier to make all
this work. (In pre-Systemd days, hacking all this
together with scripts could get very ugly.) To list all
units on your Linux installation, enter:
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Timer units: replacing Cron
Beyond system initialisation and service management, Here, the OnBootSec option tells Systemd to activate the
Systemd has its fingers in various other pies too. Notably, it unit 1 hour after the system has booted. Then the second
can perform the job of cron, arguably with more flexibility (and option means: activate the unit once a week after that. There’s
an easier to read syntax). Cron is the program that performs a huge amount of flexibility in the times that you can set –
jobs at regular intervals – such as cleaning up temporary files, enter man systemd.time for a full list.
refreshing caches and so forth. By default, Systemd’s accuracy for timing is one minute.
If you look inside the /usr/lib/systemd/system directory In other words, it will activate the unit within a minute of the PRO TIP
again, you’ll see that various .timer files are provided. Have time you specify, but not necessarily to the exact second. By default, systemctl
a look at some of them with less, and you’ll note that they This is done for power management reasons, but if you need assumes that you’re
follow a similar structure to the .service and .target files. The a timer to be executed without any delay, right down to the referring to services when
difference, however, lies in the [Timer] section. Consider this microsecond, you can add this line: issuing commands, so
example: AccuracySec=1us
you can omit the .service
bit in most cases. For
[Timer] Also, the WakeSystem option (which can be set to true or
instance, instead of
OnBootSec=1h false) defines whether or not the timer should wake up the entering systemctl status
OnUnitActiveSec=1w machine if it’s in suspend mode. gdm.service you can just
use systemctl status
gdm. The same applies
to stopping and starting
systemctl list-unit-files If you look at the unit config file in /usr/lib/ services.
Now, systemctl is the main tool for interacting with systemd/system/gdm.service, you’ll see various
Systemd, and it has many options. Here, in the unit options, including the binary to be started (ExecStart),
list, you’ll notice that there’s some formatting: enabled what it conflicts with (ie which units can’t be active at
units are shown in green, and disabled are shown in the same time), and what needs to be started before
red. Units marked as “static” can’t be started directly this unit can be activated
– they’re dependencies of other units. To narrow (the “After” line). Some
down the list to just services, use: units have additional “Systemd eschews some
systemctl list-unit-files --type=service
Note that “enabled” doesn’t necessarily mean that a
dependency options,
such as “Requires”
established Unix conventions,
service is running; just that it can be turned on. To get (mandatory such as plain text log files.”
information about a specific service, for instance GDM dependencies) and
(the Gnome Display Manager), enter: “Wants” (optional).
systemctl status gdm.service Another interesting option here is:
This provides lots of useful information: a human- Alias=display-manager.service
readable description of the service, the location of the When you activate gdm.service, you will also be
unit configuration file, when it was started, its PID, and able to view its status using systemctl status
the CGroups to which it belongs (these limit resource display-manager.service. This is useful when you
consumption for groups of processes). know there’s a display manager running, and you want
Use systemctl status,
followed by a unit name, to
see what’s going on with a
service.
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TUTORIAL SYSTEM SERVICES
dependencies of the target via the WantedBy option.
So if you look inside avahi-daemon.service,
NetworkManager.service and many other .service
files, you’ll see this line in the Install section:
WantedBy=multi-user.target
So, switching to the multi-user target will enable
those units that contain the above line. Other targets
are available (such as emergency.target for an
emergency shell, or halt.target for when the machine
shuts down), and you can easily switch between them
like so:
systemctl isolate emergency.target
In many ways, these are like SysVinit runlevels, with
text-mode multi-user.target being runlevel 3,
graphical.target being runlevel 5, reboot.target being
runlevel 6, and so forth.
Up and down
Now, you might be pondering: we’ve got this far, and
The unit configuration
to do something with it, but you don’t care whether it’s yet we haven’t even looked at stopping and starting
files might look foreign
compared to traditional GDM, KDM, XDM or any of the others. services yet! But there’s a reason for this. Systemd
scripts, but they’re not can look like a complicated beast from the outside, so
hard to grasp. Target locked it’s good to have an overview of how it works before
If you enter ls in the /usr/lib/systemd/system you start interacting with it. The actual commands for
directory, you’ll also see various files that end in managing services are very simple:
.target. A target is a way of grouping units together so systemctl stop cups.service
that they’re started at the same time. For instance, in systemctl start cups.service
most Unix-like OSes there’s a state of the system (If a unit has been disabled, you can first enable it
PRO TIP called “multi-user”, which means that the system has with systemctl enable followed by the unit name.
A simple
Xxxxx xxxway
xxxto
xxfilter
xxxx xxx booted correctly, background services are running, This places a symbolic link for the unit in the .wants
xx xxx
and manipulate
xx xxxx xxxthexxx xxx and it’s ready for one or more users to log in and do directory of the current target, in the /etc/systemd/
xx xxxx using
journal xxx xxregular
xxx xx Unix
xxxx
xxx xxtext
plain xxxtools
xx xxxx
is toxxx
usexx their work – at least, in text mode. (Other states system folder.)
journalctl
xxx xx xxxx xxx
redirection. xx xxx xx include single-user, for doing administration work, or Two more useful commands are systemctl restart
-b
xxxx> log.txt
xxx xx will
xxx place
xx xxxxxx reboot, for when the machine is shutting down.) and systemctl reload, followed by unit names. The
xxxmessages
all xx xxx xx xxxx
from xxxthe xx
xxx xx xxxx
current in log.txt,
bootxxx xx xxx xxso If you look inside multi-user.target, you may be second asks the unit to reload its configuration file.
you
xxxxcanxxxsed andxxgrep
xx xxx xxxxto expecting to see a list of units that should be active in Systemd is – for the most part – very well
your heart’s content. this state. But you’ll notice that the file is pretty bare documented, so look at the manual page (man
– instead, individual services make themselves systemctl) for details on every command.
2 LOG FILES: SAY HELLO TO JOURNALD
The second major component of Systemd is the regularly whips up heated debates on the net, but it
journal. This is a logging system, similar to syslog, but has some benefits too. For instance, logs can be more
with some major differences. And if you’re a fan of the structured, with better metadata, so it’s easier to filter
Unix way, prepare for your blood to boil: it’s a binary out information based on executable name, PID, time
log, so you can’t just parse it using your regular and so forth.
command line text tools. This design decision To view the journal in its entirety, enter:
journalctl
As with many other Systemd commands, this pipes
the output into the less program, so you can scroll
down by hitting space, use / (forward slash) to search,
and other familiar keybindings. You’ll also notice a
sprinkling of colour here too, with warnings and failure
messages in red.
That’s a lot of information; to narrow it down to the
A Systemd GUI exists, current boot, use:
although it hasn’t been journalctl -b
actively worked on for a And here’s where the Systemd journal starts to
couple of years. shine. Do you want to see all messages from the
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SYSTEM SERVICES TUTORIAL
Binary logging isn’t
popular, but the journal
has some benefits, like
very easy filtering of
information.
previous boot? Try journalctl -b -1. Or the one before If you want to narrow down to messages of a certain
that? Replace -1 with -2. How about something very priority, use the -p option. With 0 this will only show
specific, like all messages from 24 October 2014, emergency messages (ie it’s time to start praying to
16:38 onwards?” $DEITY), whereas 7 will show absolutely everything,
journalctl -b --since=”2014-10-24 16:38” including debugging messages. See the manual page
Even if you deplore binary logs, that’s still a useful (man journalctl) for more details on the priority levels. PRO TIP
feature, and for many admins it’s much easier than It’s worth noting that you can combine options as We’ve been
Xxxxx xxx xxx
mostly
xx xxxx
poking
xxx
xx xxx xx
around xxxx/usr/lib/
inside xxx xxx xxx
constructing a similar filter from regular expressions. well, so to only show messages from the GDM service systemd/system
xx xxxx xxx xx xxxinxxthisxxxx
So we’ve narrowed down the log to specific times, of priority level 3 (or lower) from the current boot, use: xxx xx xxx
tutorial, butxxyou
xxxxmay
xxx xx
but what about specific programs? For units, try this: journalctl -u gdm.service -p 3 -b xxx xxnoticed
have xxxx xxxsimilar
xx xxxfiles
xx
xxxx xxx
inside /etc/systemd/
xx xxx xx xxxxxx
journalctl -u gdm.service Finally, if you just want to have a terminal window system
xxx xx xxxas xx
well.
xxxx
What’s
xxx xx
(Note: that’s a good way to see the log generated by open, constantly updating with the latest journal xxx difference?
the xx xxxx xxx Well,
xx xxxthexx
the X server.) Or how about a specific PID? entries, as you’d have with the tail command in pre- xxxx xxx
latter takes
xx xxx
precedence,
xx xxxx
so if you have two unit
journalctl _PID=890 Systemd installations, just enter journalctl -f. files with the same names
You can even request to just see messages from a in both locations, the one
certain executable: Miked Saundersd has a PID of -1, divides by zero in his sleep, in /etc/systemd/system
and knows how to sew on a button. will be used. Generally,
journalctl /usr/bin/pulseaudio the former directory is
where installed packages
place their units, while
the latter is for units
Life without Systemd? created by root.
If you simply, absolutely can’t get on with Systemd, you still
have a few choices among the major distributions. Most
notably, Slackware, the longest-running distro, hasn’t made
the switch yet – but its lead developer hasn’t ruled it out for
the future. A few small-name distros are also holding out
with SysVinit as well.
But how long will this last? Gnome is becoming
increasingly dependent on Systemd, and the other major
desktop environments could follow suit. This is a cause
of consternation in the BSD communities, as Systemd is
heavily tied to Linux kernel features, so the desktops are
becoming less portable, in a way. A half-way-house solution
might arrive in the form of Uselessd (http://uselessd.
darknedgy.net), which is a stripped-down version of
Systemd that purely focuses on launching and supervising If you don’t like Sysytemd, try Gentoo, which has it as a
processes, without consuming the whole base system. choice of init system, but doesn’t force it on its users.
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TUTORIAL GRUB 2
GRUB 2: HEAL YOUR
TUTORIAL
BOOTLOADER
There are few things as irritating as a broken bootloader.
MAYANK SHARMA
Get the best out of Grub 2 and keep it shipshape.
T
he Grub 2 Linux bootloader is a wonderful and executed and the order of the corresponding entries
WHY DO THIS? versatile piece of software. While it isn’t the when the Grub 2 menu is built. The 00_header file is
• Grub 2 is the most only bootloader out there, it’s the most popular read first, which parses the /etc/default/grub
popular bootloader and almost all the leading desktop distros use it. The configuration file. Then come the entries for the Linux
that’s used by almost job of the Grub bootloader is twofold. First, it displays kernels in the 10_linux file. This script creates one
every Linux distribution.
a menu of all installed operating systems on a regular and one recovery menu entry for each kernel in
• A bootloader is a vital
piece of software, but computer and invites you to pick one. Second, Grub the default /boot partition.
they are susceptible to loads the Linux kernel if you choose a Linux operating This script is followed by others for third-party apps
damage. system from the boot menu. such as 30_os-prober and 40_custom. The os-prober
• Grub 2 is an expansive As you can see, if you use Linux, you can’t escape script creates entries for kernels and other operating
and flexible boot loader
that offers various the bootloader. Yet it’s one the least understood systems found on other partitions. It can recognise
customisable options. components inside a Linux distro. In this tutorial we’ll Linux, Windows, BSD and Mac OS X installations. If
familiarise you with some of Grub 2’s famed versatility your hard disk layout is too exotic for the os-prober
and equip you with the skills to help yourself when you script to pick up an installed distro, you can add it to
have a misbehaving bootloader. the 40_custom file (see the “Add custom entries” box).
The most important parts of Grub 2 are a bunch of Grub 2 does not require you to manually maintain
text files and a couple of your boot options’ configuration file: instead it
scripts. The first piece to generates the /boot/grub/grub.cfg file with the
“The Grub 2 Linux bootloader know is /etc/default/
is a wonderful and versatile grub. This is the text file
in which you can set the Graphical boot repair
piece of software.” general configuration
variables and other A vast majority of Grub 2 issues can easily be resolved with
characteristics of the Grub 2 menu (see box titled the touch of a button thanks to the Boot Repair app. This
“Common user settings”). nifty little application has an intuitive user interface and
can scan and comprehend various kinds of disk layouts
The other important aspect of Grub 2 is the
and partitioning schemes, and can sniff out and correctly
/etc/grub.d folder. All the scripts that define each identify operating system installations inside them. The
Boot Repair also lets menu entry are housed there. The names of these utility works on traditional computers with a Master Boot
you customise Grub 2’s scripts must have a two-digit numeric prefix. Its Record (MBR) as well as the newer UEFI computers with the
options. purpose is to define the order in which the scripts are UID Partition Table (GPT) layout.
The easiest way to use Boot Repair is to install it inside
a Live Ubuntu session. Fire up an Ubuntu Live distro on a
machine with a broken bootloader and install Boot Repair by
first adding its PPA repository with the
sudo add-apt-repository ppa:yannubuntu/Boot Repair
command. Then refresh the list of repositories with
sudo apt-get update
before installing the app with
sudo apt-get install -y Boot Repair
Fire up the tool once it’s installed. The app will scan
your hard disk before displaying its interface, which is
made up of a couple of buttons. To follow the advice of the
tool, simply press the Recommended Repair button, which
should fix most broken bootloaders. After it’s restored your
bootloader, the tool also spits out a small URL which you
should note. The URL contains a detailed summary of your
disks, including your partitions along with the contents
of important Grub 2 files including /etc/default/grub and
boot/grub/grub.cfg. If the tool hasn’t been able to fix your
bootloader, you can share the URL on your distro’s forum
boards to allow others to understand your disk layout and
offer suggestions.
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GRUB 2 TUTORIAL
grub2-mkconfig command. This utility will parse the
scripts in the /etc/grub.d directory and the /etc/ Grub 2 and UEFI
default/grub settings file to define your setup.
UEFI-enabled machines (more or less, any options for each removable drive – a vanilla
machine sold in the last couple of years) option and an option tagged with UEFI. Use
Bootloader bailout have added another layer of complexity to the latter to expose the EFI variables in
Grub 2 boot problems can leave the system in several debugging a broken Grub 2 bootloader. While /sys/firmware/efi/.
states. The text on the display where you’d expect the the procedure for restoring a Grub 2 install on From the live environment, mount the
bootloader menu gives an indication of the current a UEFI machine isn’t much different than it is root filesystem of the broken installation as
state of the system. If the system stops booting at the on a non-UEFI machine, the newer firmware mentioned in the tutorial. You’ll also have to
handles things differently, which results in mount the ESP partition. Assuming it’s
grub> prompt, it means the Grub 2 modules were mixed restoration results. /dev/sda1, you can mount it with
loaded but it couldn’t find the grub.cfg file. This is the On a UEFI-based system, you do not sudo mount /dev/sda1 /mnt/boot/efi
full Grub 2 command shell and you can do quite a bit install anything in the MBR. Instead you Then load the efivars module with
here to help yourself. If you see the grub rescue> install a Linux EFI bootloader in the EFI modprobe efivars before chrooting into the
prompt, it means that the bootloader couldn’t find the System Partition (ESP) and set it as the EFI’s installed distribution as shown in the tutorial.
default boot program using a tool such as Here on, if you’re using Fedora, reinstall
Grub 2 modules nor could it find any of your boot files. efibootmgr for Linux, or bcdedit for Windows. the bootloader with the
However, if your screen just displays the word ‘GRUB’, As things stand now, the Grub 2 yum reinstall grub2-efi shim
it means the bootloader has failed to find even the bootloader should be installed properly when command followed by
most basic information that’s usually contained in the installing any major desktop Linux distro, grub2-mkconfig -o /boot/grub2/grub.cfg
Master Boot Record. which will happily coexist with Windows to generate the new configuration file.
8. However, if you end up with a broken Ubuntu users can do this with
You can correct these Grub failures either by using a bootloader, you can restore the machine with apt-get install --reinstall grub-efi-amd64
live CD or from Grub 2’s command shell. If you’re lucky a live distro. When you boot the live medium, With the bootloader in place, exit chroot,
and your bootloader drops you at the grub> prompt, make sure you boot it in the UEFI mode. The unmount all partitions and reboot to the
you have the power of the Grub 2 shell at your disposal computer’s boot menu will have two boot Grub 2 menu.
to correct any errors.
The next few commands work with both grub> and
grub rescue>. The set pager=1 command invokes the fill in the name of the kernel and the initrd, which will
pager, which prevents text from scrolling off the save you a lot of time and effort.
screen. You can also use the ls command which lists Once you’ve keyed these in, type boot at the next
all partitions that Grub sees, like this: grub> prompt and Grub will boot into the specified
grub> ls operating system.
(hd0) (hd0,msdos5) (hd0,msdos6) (hd1,msdos1) Things are a little different if you’re at the grub
As you can see, the command also lists the partition rescue> prompt. Since the bootloader hasn’t been able
table scheme along with the partitions. to find and load any of the required modules, you’ll
You can also use the ls command on each partition have to insert them manually:
to find your root filesystem: grub rescue> set root=(hd0,5)
grub> ls (hd0,5)/ grub rescue> insmod (hd0,5)/boot/grub/normal.mod
lost+found/ var/ etc/ media/ bin/ initrd.gz grub rescue> normal
boot/ dev/ home/ selinux/ srv/ tmp/ vmlinuz grub> insmod linux
You can drop the msdos bit from the name of the As you can see, just like before, after we use the ls Grub 2 has a command
partition. Also, if you miss the trailing slash and instead command to hunt down the Linux partition, we mark it line, which you can invoke
say ls (hd0,5) you’ll get information about the partition with the set command. We then insert the normal by pressing C at the
including its filesystem type, total size, and last module, which when activated will return us to the bootloader menu.
modification time. If you have multiple partitions, read
the contents of the /etc/issue file with the cat
command to identify the distro, such as cat (hd0,5)/
etc/issue.
Assuming you find the root filesystem you’re looking
for inside (hd0,5), make sure that it contains the
/boot/grub directory and the Linux kernel image you
wish to boot into, such as vmlinuz-3.13.0-24-generic.
Now type the following:
grub> set root=(hd0,5)
grub> linux /boot/vmlinuz-3.13.0-24-generic root=/dev/sda5
grub> initrd /boot/initrd.img-3.13.0-24-generic
The first command points Grub to the partition
housing the distro we wish to boot into. The second
command then tells Grub the location of the kernel
image inside the partition as well as the location of the
root filesystem. The final line sets the location of the
initial ramdisk file. You can use tab autocompletion to
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TUTORIAL GRUB 2
This command will rewrite the MBR information on
the /dev/sda device, point to the current Linux
installation and rewrite some Grub 2 files such as
grubenv and device.map.
Another common issue pops up on computers with
multiple distros. When you install a new Linux distro,
its bootloader should pick up the already installed
distros. In case it doesn’t, just boot into the newly
installed distro and run
grub2-mkconfig
Before running the command, make sure that the root
partitions of the distros missing from the boot menu
are mounted. If the distro you wish to add has /root
and /home on separate partitions, only mount the
partition that contains /root, before running the
grub2-mkconfig command.
While Grub 2 will be able to pick most distros, trying
to add a Fedora installation from within Ubuntu
requires one extra step. If you’ve installed Fedora with
its default settings, the distro’s installer would have
created LVM partitions. In this case, you’ll first have to
install the lvm2 driver using the distro’s package
management system, such as with
sudo apt-get install lvm2
before Grub 2’s os-prober script can find and add
Fedora to the boot menu.
To disable a script under
the /etc/grub.d, all you
standard grub> mode. The next command then Thorough fix
need to do is remove the inserts the linux module in case it hasn’t been loaded. If the grub2-install command didn’t work for you, and
executable bit, for example Once this module has been loaded you can proceed to you still can’t boot into Linux, you’ll need to completely
with point the boot loader to the kernel image and initrd reinstall and reconfigure the bootloader. For this task,
chmod -x /etc/grub.d/20_ files just as before and round off the procedure with we’ll use the venerable chroot utility to change the run
memtest86+ the boot command to bring up the distro. environment from that of the live CD to the Linux
which will remove the Once you’ve successfully booted into the distro, install we want to recover. You can use any Linux live
‘Memory Test’ option from don’t forget to regenerate a new configuration file for CD for this purpose as long as it has the chroot tool.
the menu.
Grub with the However, make sure the live medium is for the same
grub-mkconfig -o /boot/grub/grub.cfg architecture as the architecture of the installation on
command. You’ll also have to install a copy of the the hard disk. So if you wish to chroot to a 64-bit
bootloader into the MBR with the installation you must use an amd64 live distro.
sudo grub2-install /dev/sda After you’ve booted the live distro, the first order of
command. business is to check the partitions on the machine.
Use fdisk -l to list all the partitions on the disk and
Dude, where’s my Grub?
The best thing about Grub 2 is that you can reinstall it
Common user settings
whenever you want. So if you lose the Grub 2
bootloader, say when Grub 2 has lots of configuration variables. Here are some of
another OS like Windows the common ones that you’re most likely to modify in the
“The best thing about Grub 2 replaces it with its own
/etc/default/grub file. The GRUB_DEFAULT variable specifies
the default boot entry. It will accept a numeric value such as
is that you can reinstall it bootloader, you can
restore Grub within a few
0, which denotes the first entry, or “saved” which will point
whenever you want.” steps with the help of a
it to the selected option from the previous boot. The GRUB_
TIMEOUT variable specifies the delay before booting the
live distro. Assuming default menu entry and the GRUB_CMDLINE_LINUX variable
lists the parameters that are passed on the kernel command
you’ve installed a distro on /dev/sda5, you can
line for all Linux menu entries.
reinstall Grub by first creating a mount directory for If the GRUB_DISABLE_RECOVERY variable is set to true,
the distro with the recovery mode menu entries will not be generated.
sudo mkdir -p /mnt/distro These entries boot the distro into single-user mode from
and then mounting the partition with where you can repair your system with command line tools.
Also useful is the GRUB_GFXMODE variable, which specifies
mount /dev/sda5 /mnt/distro
the resolution of the text shown in the menu. The variable
You can then reinstall Grub with can take any value supported by your graphics card.
grub2-install --root-directory=/mnt/distro /dev/sda
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GRUB 2 TUTORIAL
make note of the partition that holds the Grub 2
installation that you want to fix. Add custom entries
Let’s assume we wish to restore the bootloader If you wish to add an entry to the bootloader }
from the distro installed in /dev/sda5. Fire up a menu, you should add a boot stanza to the For more accurate results, instead of
terminal and mount it with: 40_custom script. You can, for example, device and partition names you can use their
use it to display an entry to boot a Linux UUIDs, such as
sudo mount /dev/sda5 /mnt
distro installed on a removable USB drive. set root=UUID=54f22dd7-eabe
Now you’ll have to bind the directories that the Grub 2 Assuming your USB drive is sdb1, and the Use
bootloader needs access to in order to detect other vmlinuz kernel image and the initrd files are sudo blkid
operating systems: under the root (/) directory, add the following to find the UUIDs of all the connected drives
$ sudo mount --bind /dev /mnt/dev to the 40_custom file: and partitions. You can also add entries for
menuentry “Linux on USB” { any distros on your disk that weren’t picked
$ sudo mount --bind /dev/pts /mnt/dev/pts
set root=(hd1,1) up by the os-prober script, as long as you
$ sudo mount --bind /proc /mnt/proc linux /vmlinuz root=/dev/sdb1 ro quiet splash know where the distro’s installed and the
$ sudo mount --bind /sys /mnt/sys initrd /initrd.img location of its kernel and initrd image files.
We’re now all set to leave the live environment and
enter into the distro installed inside the /dev/sda5
partition via chroot: order:
$ sudo chroot /mnt /bin/bash $ exit
You’re now all set to install, check, and update Grub. $ sudo umount /mnt/sys
Just like before, use the $ sudo umount /mnt/proc
sudo grub2-install /dev/sda $ sudo umount /mnt/dev/pts
command to reinstall the bootloader. Since the $ sudo umount /mnt/dev
grub2-install command doesn’t touch the grub.cfg $ sudo umount /mnt
file, we’ll have to create it manually with You can now safely reboot the machine, which
sudo grub-mkconfig -o /boot/grub/grub.cfg should be back under Grub 2’s control, and the
That should do the trick. You now have a fresh copy bootloader under yours!
of Grub 2 with a list of all the operating systems and
distros installed on your machine. Before you can Mayank Sharma has been tinkering with Linux since the 90s
restart the computer, you’ll have to exit the chrooted and contributes to a variety of technical publications on both
sides of the pond.
system and unmount all the partitions in the following
www.linuxvoice.com 93
CODING ATLAS: THE UK’S SUPERCOMPUTER
ATLAS: THE UK’S
TUTORIAL
SUPERCOMPUTER
JULIET KEMP
In the 1950s came the transistor, and with the transistor came the
supercomputer – here’s how to program one of the first.
A
tlas, in Manchester, was one of the first 1955.) Once junction transistors became available, the
supercomputers; it was said that when Atlas second version of the machine was more reliable.
went down, the UK’s computing capacity was
reduced by half. Today supercomputers are massively Building Atlas
parallel and run at many, many times the speed of After the success of the Transistor Computer, the next
Atlas. (The fastest in the world is currently Tianhe-2, in challenge the team set themselves was to build a
Guangzhou, China, running at 33 petaflops, or over a “microsecond engine” – a computer that could
thousand million times faster than Atlas.) But some of operate at one microsecond per instruction (or close
the basics of modern computers still owe something to it), so managing a million instructions a second.
to the decisions made by the Atlas team when they (This is not quite the same as one megaflop, as
were trying to build their ‘microsecond engine’. FLOPS measure floating-point operations, not
The computers of the early 1950s were built with instructions, and are a little slower than instructions.)
vacuum tubes, which made for machines which The machine was initially called MUSE (after the
were enormous, unreliable, and very expensive. The Greek letter μ, meaning one-millionth), but was
University of Manchester computing team already renamed Atlas once the Ferranti company became
had one of these, the Manchester Mark 1 (which involved in 1958. When Atlas was officially first
Alan Turing worked with), which began operation in commissioned, in December 1962, it was one of the
April 1949. They were working on a smaller version most powerful computers in the world, running at (at
when Tom Kilburn, director of the group, set a couple peak) 1.59 microseconds per instruction, or around
of his team to designing 630,000 instructions/second.
“Germanium transistors were a computer which used
transistors.
Atlas was an asynchronous processing machine,
with 48-bit words, 24-bit addressing, and (in the
even less reliable than valves, The result was the Manchester installation) 16k word core store and 96k
but were a lot cheaper to run.” Transistor Computer, the
world’s first transistorised
word drum store. It also had over a hundred index
registers to use for address modification. It was fitted
computer, first operational up for magnetic tape (a big novelty at the time and
in April 1953. It used germanium point-contact much faster than paper tape).
transistors, the only type available at the time, which One important feature was instruction pipelining,
were even less reliable than valves; but they were a lot which meant being able to speed up programs
The University of
cheaper to run, using much less power. It did still use beyond merely running instructions more quickly. With
Manchester’s ATLAS
machine, photographed valves for memory read/write and for the clock cycle, instruction pipelining, the CPU begins to fetch the next
on 1 January 1963. Photo: so it wasn’t fully transistorised. (The first fully instruction while the current one is still processing.
Iain MacCallum transistorised computer was the Harwell CADET, in Instead of holding up the whole CPU while a single
instruction goes through the CPU’s various parts,
pipelining means that instructions follow one another
from point A to point B to point C through the CPU,
maximising the amount of work being done by the
CPU at a particular time, and minimising the overall
time. Obviously this does require appropriate
programming to take advantage of it.
Atlas’ “Extracode” setup also allowed certain more
complex instructions to run as software rather than
be included in the hardware. The most significant bit
of the top 10 bits of a word determined whether an
instruction was a normal hardware instruction, or an
Extracode instruction. An Extracode instruction meant
that the program would jump to what was basically a
subroutine in the ROM, and run that. This was a way
of reducing the complexity of the hardware while still
94 www.linuxvoice.com
ATLAS: THE UK’S SUPERCOMPUTER CODING
being able to provide those complicated instrutions
‘baked in’ to the machine (and thus easy to use for Transitors
programmers). Extracode instructions were used
Vacuum tubes, used in all the 1940s slightly impure becomes a semiconductor,
particularly for calculations like sine/cosine and
computers, were far from ideal. Everyone which is what is needed for a transistor
square root (inefficient to wire into the hardware); but in the industry was keen for something to work. The amount of impurity must be
they were also used for operating system functions different. In particular, Bell (the telephone tightly controlled to create the correct effect.
like printing to output or reading from a tape. (See the company) wanted a more reliable component Germanium transistors were very quickly
next section for more on the Atlas Supervisor.) for telephone systems. It put together a replaced by junction transistors, which are
team to research transistors, based on an more robust and easier to make.
The first production Atlas, the Manchester
idea patented in the late 1920s by physicist Transistors are an essential part of nearly
installation, started work in 1962, although the OS Julius Lilienfeld. The Bell Labs team all modern electronics, although most
software, Atlas Supervisor (see below) wasn’t fully produced a working transistor in 1947 (a modern transistors are silicon rather than
operational until early 1964. Ferranti and the French team repeated this independently germanium. The fact that they can be easily
University shared the available time on Atlas, running in 1948). Bell Labs’ Shockley, Bardeen, and mass-produced at low cost (more than ten
Brattain won the Nobel Prize in Physics in million transistors can be made per US cent)
between them up to a thousand user programs in a
1956 for their work. has been a crucial part of the development
20-hour ‘day’. The value of the machine to the Fundamentally, transistors control and of mass modern technology. These days they
University was estimated at £720,000 per year in direct the flow of electricity. They act as are usually part of an integrated circuit rather
1969, if they’d had to buy it in externally. switches (sending current one way or than wired together as with early transistor
another, or switching it off), and they can computers, but they’re still at the core of all
also amplify current, making the output practical electronics. Estimates of transistors
Software
power greater than the input power. The first made per year vary between about half a
A 48-bit Atlas instruction was divided into four parts: a transistors were made from germanium, billion and a billion per person on the Earth,
10-bit function code, 7-bit Ba (bits 10-16) and 7-bit Bm which when pure is an insulator, but when and those numbers are still going up.
(bits 17-25) index registers, and a 24-bit address.
There were two basic types of instruction: B-codes,
which used Bm as a modifier and Ba as a register potentially onto many different devices, maintaining a
address and did integer operations; and A-codes, list of documents to be output.
which provided floating point arithmetic. One of the radical innovations of Atlas was virtual
The B index registers were used to modify the given memory. Computers had (and still have) two levels of
address to get the ‘correct’ one (useful for moving memory: main (working) memory and secondary
through a series of memory locations); having two (disk; or drums/tapes back in the 1950s) memory. A
index fields meant Atlas could be double-indexed. You program can only deal directly with main memory. For
could also test the Bm register and then do something a programmer trying to perform a calculation (such as Ann Moffat worked with
specific with the contents of the Ba register, matrix multiplication) that couldn’t fit into main Ferranti on the Manchester
depending on the result of the test. Specifically, there memory, a large part of the job became working out Atlas from 1962, and
was a general form of: how to switch data in and out of secondary memory, in 1966 was one of the
“if CONDITION then load register Ba with address N how to do it most efficiently, what blocks (pages) to earliest teleworkers – here
(and optionally act on Bm); otherwise do nothing” divide it into, how to swap it in and out, and so on. The seen writing programs to
Since register B127 was the program counter, this designers of Atlas were working programmers (as analyse Concorde’s black
was everyone working in computers at the time), and box, with her daughter.
could be used as a program operation transfer. Simply
Copyright Rutherford
set N to the location you want to jump to, and set Ba it was very clear to them that automating this process
Appleton Laboratory
to B127. If the condition is true, B127 now contains would make programmers’ lives much easier. Atlas’ and the Science and
address N, and the program jumps to N. virtual memory had three important features: Technology Facilities
Other B registers also had specific roles, and there It translated addresses automatically into memory Council (STFC). www.
is a comprehensive list of these registers and many locations (so the programmer didn’t need to keep chilton-computing.org.uk.
other details of the system in the short book The Story
of ATLAS by Iain Stinson (http://elearn.cs.man.ac.
uk/~atlas/docs/london%20atlas%20book.pdf).
Atlas Supervisor was the Atlas operating system,
which managed resources and allocated them
between user programs and other tasks, including
managing virtual memory. It’s been called “the first
recognisable modern OS” in terms of how it managed
jobs and resources. At any given time, multiple user
programs could be running, and it was Atlas
Supervisor’s responsibility to manage resources and
workload. The Scheduler and Job Assembler would
assemble all parts of a job and sort it into one of two
queues (requires its own magnetic tape, or does not).
The Central Executive took care of program-switching,
error-monitoring, Extracodes, and memory
management. Output Assembly handled output
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CODING ATLAS: THE UK’S SUPERCOMPUTER
compile.) Next, go to Project > Properties > Compiler,
and make sure that the Hase directory is set correctly
to where you installed HASE. Finally, hit the Compile
and Build buttons on the menu bar.
Having compiled the code, you can run it (with the
green running person icon), then load the tracefile
back into the simulator and watch it run (use the clock
icon, and choose the relevant results file). Run it to
watch changes happen in the simulated construction.
You can also watch the pipelining happen, and the
virtual pages being requested and loaded.
If you want to look at the program instructions
themselves, they are found in the DRUM_STORE.
pageX.mem files in the model directory, starting with
page 0. They are structured as:
instruction Ba Bm address
track of memory locations by hand). The Drum Store contains the program code in page
The Atlas machine room at
It had demand paging: the address translator would 0, fixed-point integers in page 2, and floating-point
Chilton in 1967. Copyright
Rutherford Appleton automatically load a required page of data into main reals in page 3. The Core Store is empty at the start of
Laboratory and the memory when it was required. the simulation, with Block 0 modelled as an
Science and Technology It had an algorithm which identified the currently instruction array, Block 1 as an integer array, and Block
Facilities Council (STFC). least-required pages and moved them back into 2 as a floating-point array. As each array of code/
www.chilton-computing. secondary memory. integers/floating-point number is needed, it is fetched
org.uk. Fundamentally, this is still what virtual memory in from the Drum Store.
does today, and it does, as expected, make For an explanation of the instructions used in each
programming massively more straightforward. It’s model, check out the HASE Atlas simulation webpage
also vital for running multiple programs at the same (www.icsa.inf.ed.ac.uk/cgi-bin/hase/atlas.pl?menu.
time, allowing the OS to swap parts of jobs in and out html,atlas.html), which also has more details of the
of memory as they are required. simulation itself. The listing of the first demonstration
program doubles as a list of Atlas instructions.
Emulator You can also try the other demonstration programs,
An Atlas simulator is available from the Institute for both of which do actual mathematics. V3.2 is a Sum
Computing Systems Architecture (University of of Squares program, which should report in the
Edinburgh – www.icsa.inf.ed.ac.uk/research/ Output window the result 3, 4, 5, (then print stopping).
groups/hase/models/atlas/index.html). You can This is the solution of the equation a2 + b2 = c 2 for a,
download their three sample programs from their b, c < 8. We couldn’t find any output for the Matrix
website. This is a simulator rather than an emulator, in Multiplication program (updates would be welcome if
that it simulates the operation of the Atlas any readers do experiment with it!). An explanation of
architecture by modelling its internal state, but doesn’t the model is at the link above.
pretend to give the experience of operating the whole More information about HASE, a user guide, and
machine. how to create your own models, is available here:
To run the simulator, you’ll first need to download www.icsa.inf.ed.ac.uk/research/groups/hase/
and install HASE III. There are detailed instructions manuals/index.html.
www.icsa.inf.ed.ac.uk/research/groups/hase/
models/use.html, but basically you download the jar Building your own program
file, then type: If you copy the contents of one of the sample
java -jar Setup_HASE_3.5.jar directories wholesale into another directory, and
at a terminal window. Run as root to be able to install rename atlas_v*.* to my_project.* (so you’re
for all users of the machine, or as a user to install for renaming the .edl .elf .params files), you can edit the
just that user. You can then run the bin/Hase DRUM_STORE.page0.mem file to produce your own
executable from wherever you installed the program. small program. Here’s one example:
To run one of the Atlas projects, download one of A314 0 0 12288
the samples and unzip it, choose Open Project from A320 0 0 12296
the HASE menu, then choose the relevant .edl file. So A346 0 0 12304
for Atlas_V1.3, the project that demonstrates each of STOP
the various instructions, choose V1.3/atlas_v1.3.edl. nop 0 0 0 ... to end of file (must be 256 lines)
To compile the project, first, if you installed HASE as This loads the value in word 1536 into the
root, you’ll need to make sure that the user as which accumulator (A314), adds the value in word 1537 to it
you’re running has write access to hase/hase-iii/lib. (A320), and then stores the result in word 1538
(This seems only to be necessary for the first (A346). Words 1536 onwards are found at the start of
96 www.linuxvoice.com
ATLAS: THE UK’S SUPERCOMPUTER CODING
The simulator after running
DRUM_STORE.page3.mem, and are loaded into the that won’t load! Two more Atlas machines were built
the v1.3 model. The blue
core store block 2 when needed. alongside the Manchester one; one shared by BP and fast-forward button runs
To run it, load the project, compile it, run, and then the University of London, and one for the Atlas the whole thing as fast as
you can watch the trace. If editing, reload the project, Computer Laboratory in Chilton near Oxford, which possible. The green button
then recompile. provided a shared research computing service to allows you to watch more
Here’s the same example (adding two numbers) in British scientists. slowly, or you can step
B-instructions: through one process at a
B121 1 0 3 After Atlas time.
B124 2 1 4 Ferranti also built a similar system, called Titan (aka
E1064 0 0 0 Atlas 2), for Cambridge University. Its memory was
E1067 2 0 0 organised a little differently, and it ran a different OS
STOP written by the Computer Lab folk at Cambridge. Titans
This loads the value 3 (not a memory address) into were also delivered to the CAD Centre in Cambridge,
B1 in line 0 (B121), then in line 1 adds 4 modified by and to the Atomic Weapons Establishment at
PRO TIP
the contents of B1 to B2: Aldermaston. The Manchester Atlas was
There is an emulator
B124 B-register B-modification-register Number decommissioned in 1971, and the last of the other
(which copies external
So in practice this adds 4 + B1 = 4 + 3 = 7 to B2 two closed down in 1974. The Chilton Atlas main behaviour) of the whole
(which starts as zero). Line 2 uses an Extracode console was rediscovered earlier this year and is now thing available, but it’s
Windows-only; see Dik
instruction: at the Rutherford Appleton Laboratory in Chilton;
Leatherdale’s webpage
E1064 National Museums Scotland in Edinburgh also has a at www.dikleatherdale.
to output a newline, then line 3 uses another couple of its parts. The Titans closed down between webspace.virginmedia.
com/atlas.html.
Extracode instruction: 1973 and 1974.
E1067 The Atlas team were responsible for the start of
to output the contents of B2. numerous concepts (such as pipelining, virtual
You can see the output 7 in the bottom window, memory and paging, as well as some of the OS ideas
and in the main window, the 7 in the process of being behind Atlas Supervisor) which are still important in
returned to Control as part of instruction 1. modern computing; and, of course, at the time, the
As mentioned above, the first test program listing in machines themselves were of huge research
the Atlas model information (www.icsa.inf.ed.ac.uk/ importance. It’s rather a shame that it seems largely
cgi-bin/hase/atlas.pl?menu.html,atlas.html) is to have been forgotten in the shadow of other
effectively an instruction listing. The earlier B supercomputers such as those made by Cray and by
instructions, for example, access memory locations IBM. It was certainly a very successful British project
rather than absolute values. Remember that A at the time.
instructions managed floating point operations, and B In 2012, Google produced a short film remembering
instructions the integer operations. This means that A the Atlas, which is available online. There’s also a
instructions operate only on the floating-point values collection of links and memories available on the
(from block 2 of the core store, word 1536 onwards, Manchester University website. There’s some
memory location 12288 onwards), and B instructions documentation on the Chiltern Computing website,
only on integers (block 1 of the core store, word 1024 too, including this brochure from 1967
onwards, location 8192 onwards). We’re not sure to (www.chilton-computing.org.uk/acl/literature/acl/
what extent this exactly mirrors the real setup of Atlas p003.htm).
memory and to what extent it is a feature of the
organisation of the simulator, but do bear it in mind to Juliet Kemp is a scary polymath, and is the author of
O’Reilly’s Linux System Administration Recipes.
avoid getting really frustrated with memory locations
www.linuxvoice.com 97
CODING MANDELBROT & PYTHON
PYTHON: MAKE YOUR
TUTORIAL
OWN JULIA FRACTALS
TARIQ RASHID
With a smattering of Python and some clever maths you can create
even more beautiful chaos inside your Linux box.
J
ulia sets are closely related to the Mandelbrot
Set, which we explored last issue with some
basic Python. All of these are produced by the
code we’ll develop here from the same simple iterated
function z2+c as the Mandelbrot fractals.
You can see that they are different to the
Mandelbrot set, and yet there’s something about
them that is similar. You can also see that some
Julia sets are a single object like the Mandelbrot, but
PRO TIP some are many pieces, with some even becoming so
Explore the Mandelbrot fragmented they are almost like dust.
and Julia fractals using
the interactive XaoS open
It might not be obvious, but while there is only one
source software at http:// Mandelbrot, there are infinitely many Julia sets. The Just one look tells you that the Julia set is very closely
bit.ly/1vLdz52 or through recipe, or algorithm, for creating Julia sets is the same related, but subtly different to the Mandelbrot set.
a web browser http://bit.
ly/1lbXYL1
as that for the Mandelbrot set except for one key
difference. pass
Let’s remind ourselves of the recipe for the pass
Mandelbrot set. We choose a rectangle on the return iteration
complex plane and test many evenly spaced points You can see that z doesn’t start at (0+0i) anymore
to see whether they’re part of the Mandelbrot set. We but is a parameter passed to the function. The
do this by seeing if repeated iteration of a function parameter c is also passed but is a fixed complex
z2+c, where c is the point being tested, results in the number and not a number representing the point
orbit escaping and diverging, or not. And if it does, being tested, because z does that now.
we colour the point according to how fast the point The Python program to plot Julia sets is presented
diverges. here for easy reference:
This recipe is essentially the same for making Julia # loads the numerical and plotting extensions to Python
Instead of c representing sets. The difference is that the roles of the z and c # needed if you’re using a locally installed IPython, not for some
the point on the complex values are reversed (see diagram below). online IPython providers
being tested (as in the The following shows the calculating function julia(z, %pylab inline
Mandlebrot set), it is kept c, maxiter), based on the mandel(c, maxiter) function
constant for all the points we developed in the last issue: # set the location and size of the atlas rectangle
being tested. Similarly
def julia(z, c, maxiter): xvalues = linspace(-2, 2, 1000)
instead of z starting
for iteration in xrange(maxiter): yvalues = linspace(-2, 2, 1000)
from zero, it starts as
the complex number z = (z*z) + c
representing the point if abs(z) > 4: # size of these lists of x and y values
being tested. break xlen = len(xvalues)
ylen = len(yvalues)
Mandelbrot set Julia set
# value of c (unique for each Julia set)
c = complex(-0.35, 0.65)
2
Iterate z + c
# julia function, takes the fixed parameters z and c and the
maximum number of iterations maxiter, as inputs
def julia(z, c, maxiter):
Different c # start iterating and stop when it’s done maxiter times
Different z
C is point on rectangle being Z is point on rectangle being for iteration in xrange(maxiter):
tested, varies across rectangle tested, varies across rectangle
Z starts at zero (0+01) C is fixed for this Julia set # the main function which generates the output value of z
from the input values using the formula (z^2) + c
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MANDELBROT & PYTHON CODING
z = (z*z) + c
# check if the (pythagorean) magnitude of the output
complex number z is bigger than 4, and if so stop iterating as
we’ve diverged already
if abs(z) > 4:
break
pass
pass
# return the number of iterations we actually did, not the final
value of z, as this tells us how quickly the values diverged past
the magnitude threshold of 4
return iteration
# create an array of the right size to represent the atlas, we use
the number of items in xvalues and yvalues
atlas = empty((xlen,ylen))
Some Julia fractals
# go through each point in this atlas array and test to see how are more broken up,
many iterations are needed to diverge (or reach the maximum pass
while others are more
contiguous.
iterations when not diverging) pass
for ix in xrange(xlen):
for iy in xrange(ylen): # set the figure size
figsize(18,18)
# at this point in the array, work out what the actual real and
imaginary parts of x are by looking it up in the xvalue and yvalue # plot the array atlas as an image, with its values represented as
lists colours, peculiarity of python that we have to transpose the
zx = xvalues[ix] array
zy = yvalues[iy]
z = complex(zx, zy) imshow(atlas.T, interpolation=”nearest”)
Try plotting different Julia sets by changing the c
# now we know what c is for this place in the atlas, apply the parameter. Remember it is the single parameter c
mandel() function to return the number of iterations it took to which uniquely defines the Julia set.
diverge
# we use 80 maximum iterations to stop and accept the 3D fractal landscapes
function didn’t diverge This section will require you to use a locally installed
atlas[ix,iy] = julia(z,c,80) version of IPython, because the online IPython services
can’t access your OpenGL graphics subsystem to PRO TIP
render the three-dimensional plots.
Pretty as a picture Let’s try to turn the two-dimensional flat images of
The code for the full
programs to calculate and
Here’s an image produced by one of the filters provided by the Mandelbrot and Julia sets into three dimensions. plot the Mandelbrot and
One way to do this is to use the colour information in Julia fractals is online at
the same extension that we got the Gaussian filter from. It’s
http://bit.ly/1qpnlsE.
beautiful – and is the cover of the author’s ebook (http:// each image array to represent altitude; the height of a
www.amazon.co.uk/Make-Your-Mandelbrot-Tariq-Rashid- landscape above sea level as it were. We should then
ebook/dp/B00JFIEC2A). See if you can recreate it yourself.
see mountainous landscapes shaped by the values of
The image is the result of a filter that highlights edges
(a Sobel filter) applied to the same Julia images we created arrays filled by the Mandelbrot or Julia calculations.
previously. The code is at http://bit.ly/1qpnlsE.
Surface plot
Let’s try it on a very simple array first. The following
code prepares a 3x2 array:
a = zeros( [3,2] )
a[0,0] = 1
a[0,1] = 2
a[1,0] = 4
a[2,1] = 3
print a
Plotting a simple flat image based on these values,
using imshow(a, interpolation=”nearest”) results in
the simple 2D plot as expected.
www.linuxvoice.com 99
CODING MANDELBROT & PYTHON
Now let’s plot this same array in three dimensions, three-dimensional plots, remembering to import the
with the third dimension given by the value of each mayavi extension too. It’s worth keeping the previous
cell. To do this we need to use a new extension to imshow() instruction to see the flat view too. The
Python called mayavi. instructions are as follows. The warp_scale was
Telling IPython that we want to use mayavi uses adjusted to 1.0 to give a reasonable height, the default
the import instruction, just as before. The special setting created hills that were a little too steep:
paylab instruction is to ensure that the common set mayavi.mlab.surf(atlas.T, warp_scale=1.0)
PRO TIP of numerical extensions are automatically loaded in mayavi.mlab.show()
Don’t forget that in the local IPython: These three-dimensional height fields as some
Python, like many %pylab inline people call them, give an interesting perspective of the
programming langauges,
counting elements of import mayavi.mlab Mandelbrot set.
arrays and lists starts at The instructions to plot a surface are simple: Let’s try that again but with the original rectangle
0 not 1. mayavi.mlab.surf(a, warp_scale=”auto”) zooming into details of the Mandelbrot set, and also
mayavi.mlab.show() change the colour palette by using the interactive
The first instruction prepares the surface plot and menus. Some of these landscapes are quite haunting.
allows IPython to automatically scale the heights. The Let’s try the same idea with Julia sets.
second instruction is needed to actually show the plot.
This time the result will appear in a separate window Gentler landscapes
outside your browser. You can do quite a lot to this Some of the landscapes we created were a little spiky
3D plot, including rotating it around and changing the and noisy. Let’s see if we can calm them down,
lighting that illuminates it. The images at the bottom smooth off the sharp edges, and reduce the
of the page show the above small array plotted in cragginess a little, all in the hope of creating a perhaps
this way, and again rotated using the mouse. Try it more gentle, more appealing, landscape.
yourself. One way to do this is to calculate a new image
For easy reference, the entire code for creating a array, based on the original one, but with each new
simple 3x2 array and plotting a three-dimensional plot value somehow smoothed based on its neighbour’s
of it as as follows: values. We want to calculate the average over a small
%pylab inline group of neighbouring array elements, perhaps a 3x3
import mayavi.mlab square or a bigger circle. Engineers and scientists who
work with images or signals do this kind of thing fairly
a = zeros( [3,2] ) often to try to reduce noise.
a[0,0] = 1 Python provides a collection of such filters that can
a[0,1] = 2 be applied to an array of values, which is often useful
a[1,0] = 4 when they are in fact images. A common smoothing
PRO TIP a[2,1] = 3 filter is a slightly more sophisticated version of the
You can explore these 3D local average we just described, called a Gaussian blur
views by rotating them mayavi.mlab.surf(a, warp_scale=”auto”) filter. If you work with photo editing applications like
and dragging them with mayavi.mlab.show() Photoshop or Gimp then you’ll be familiar with applying
your pointer, and use the
menus to select different We now apply this same idea to the larger arrays a Gaussian blur to smooth an image.
ligthting, colour palettes created by the Mandelbrot code we wrote earlier. To get access to these filters, we’ll need to import
and many other options. We simply add the new instructions to create the the Python extension at the top of our code as follows:
Small rotated and
illuminated 3D plotted
array.
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MANDELBROT & PYTHON CODING
The intimate relationship between Mandelbrot and Julia fractals
The Mandelbrot and Julia fractals are intimately fractals are a single object. For values of c that Julia set
connected. The relationship is illustrated in the fall outside the Mandelbrot, the Julia fractals are
following diagram. Each Julia fractal is uniquely many separate pieces. The further c moves from the
defined by the chosen value of c in z2+c. For values Mandelbrot set, the more fragmented and dust-like
of c that fall inside the Mandelbrot fractal, the Julia the Julia fractals become.
Julia set Mandelbrot set
Connected (all in one piece)
Julia set for c inside the
Mandelbrot set
Very disconnected dust-like
Julia set for c away from the Julia set
Mandelbrot set.
More bulbous, more
connected Julia set for c
closer to the Mandelbrot set.
import scipy.ndimage imshow(smoothed_atlas, interpolation=”nearest”)
The following shows how the Gaussian blur filter Similarly we can plot the 3-dimensional landscape
can be used to create a smoothed image array from just as before using the mayavi extensions.
the original, which we called atlas in our previous mayavi.mlab.surf(smoothed_atlas, warp_scale=0.9)
code. The value 2 is the strength of the smoothing: mayavi.mlab.show()
smoothed_atlas = scipy.ndimage.gaussian_filter(atlas.T, 2) We’d suggest playing with the settings for the
We can plot this as a flat image just as before using Gaussian smoothing filter to get an effect that works
the imshow function: for you. For example, we’ve had great results applying
# set the figure size the filter to the Julia set generated by c=(-0.768662 +
figsize(18,18) 0.130477i), but there are many different variations and
many kinds of smoothing effects you can produce.
# create a smoothed image of the original by applying a
Gaussian blur filter Try It Yourself
smoothed_atlas = scipy.ndimage.gaussian_filter(atlas.T, 2) We’d encourage you to explore other filters to see if
# plot the array atlas as an image, with its values represented as they make interesting images. Perhaps you might
colours, peculiarity of python that we have to transpose the explore different functions aside from z2+c which was
array the basis for both the Mandelbrot and Julia fractals. PRO TIP
And remember, you can’t do any harm by You can explore more
filters, besides the
experimenting and playing. We hope in this series of Gaussian blur, to apply to
tutorials you’ve discovered the fun and convenient your images at http://bit.
IPython environment for web-based Python ly/1mNyMWE
programming, and become familiar with the basic
building blocks of Python programming. We also hope
you’ve experienced some of the surprise, excitement
and beauty that even simple mathematics holds,
particularly if your experience has been of boring
trigonometry puzzles. Now go and play with some
maths!
Tariq spends his time grappling with enterprise IT problems,
Add a 3D height field and a Gaussian blur to our informed by two decades of working with open technology.
Mandelbrot image and you get the Misty Mountains.
www.linuxvoice.com 101
CODING NINJA
CODE NINJA:
TUTORIAL
STDIN AND STDOUT
Make your Python programs work with the Linux shell to build
BEN EVERARD
your own command line utilities.
I
f you’ve used the Linux command line for more
WHY DO THIS? than the most basic uses, you’ll be familiar with
• Understand one of the concepts of standard in (stdin) and standard
the basic principles of
how the command line out (sdtout). These are channels the shell pushes
works. data through when you link commands with the pipe
• Write your own utilities character (|). For example :
for the Linux shell. dmesg | grep “USB”
• Get more out of Python. Here, the first command (dmesg) sends the kernel
message buffer to stdout. The | symbol takes the
stdout of one command and pushes it into the stdin
of the next. The grep command then goes through
each line in its stdin and prints out only those
containing the string ‘USB’. Using this concept of stdin
and stdout, we’ve managed to build a simple little tool
for checking the kernel messages about USB devices.
In the Unix philosophy, as much as possible, GNU’s cat utility has many more features than we’ve
programs should be simple commands that work implemented here, but it still works on the same basis of
with stdin and stdout. If they do, then they can be reading files and sending their contents to stdout.
combined with the other Unix commands in a huge
number of ways. Working this way means you can Each line that we read from the file includes the
focus your program on newline character at the end, so we include the
“In Unix, programs should be doing one thing well. Rather
than having to program
parameter end=”” to stop the print function from
adding a separate newline character which would
simple commands that work every possible feature, you leave a blank line between every line form the file.
with stdin and stdout.” just focus on the core of the
program and the user can In and out
use other Unix tools to gain We can get the arguments to the command from
more features by chaining commands together. sys.argv. This is simply a list of everything that’s
Let’s take a look at how we could start building our supplied to the Linux Shell (see “Arguments” box).
own implementations of standard Unix tools in Here, we just use this to loop through every argument
Python that interact using stdin and stdout so they to the command and hope it’s a file. So, the following
can be chained together. would send the output of file1 and file2 to stdout:
Let’s start with cat. This stands for catenate. python cat.py file1 file2
Basically, it’s used to send the output of one or more You can chain this with other Unix commands such
files to stdout. In Python, this is really easy: as wc (word count) like this:
from __future__ import print_function python cat.py /usr/share/dict/words | wc
import sys wc outputs the number of lines, words and characters
in a file. Let’s implement that next:
for arg in sys.argv[1:]: from __future__ import print_function
with open(arg) as file: import sys
for line in file:
print(line, end=””) num_lines = 0
All we have to do to send something to stdout in num_words = 0
Python is print it. Here we’ve used the print function, num_chars = 0
which is the standard way of doing it in Python 3. This
also works in Python 2 if you include the first import for line in sys.stdin:
line. The reason we’ve done it this way is because we’ll num_lines += 1
use some features of the print function a little later on, num_words += len(line.split())
and want to keep things consistent. num_chars += len(line)
102 www.linuxvoice.com
NINJA CODING
Arguments
Interacting nicely with the Linux command line environment parser.add_argument(‘echo’, help=’The stuff to print on screen’)
isn’t all about using stdin, stdout and stderr. Another aspect parser.add_argument(“--stderr”, help=”print the stuff to stderr
of the command line environment is properly parsing (otherwise print to stdout)”, action=”store_true”)
arguments and flags. For example, in the cat Python script, we args = parser.parse_args()
take a list of files as arguments. We did this using sys.argv. if args.stderr:
This provides a list of everything that’s passed to the print(args.echo, file=sys.stderr)
command (the first item in the list is the command itself; in else:
that example, we only included everything from the second print(args.echo)
element onwards). You can now check it’s working with the following lines:
However, if your command takes a range of options, it can python echo.py --stderr “hello world” | wc
be quite complex to correctly parse this. Fortunately, there’s a python echo.py “hello world” | wc
module to help: argparse. Let’s take a look at a simple The argparser module even takes care of creating your help
example. This will be a command a little like echo, but it will text (from the description and help parameters used when
send the output to stdout unless the --stderr flag is present, in creating the parser), so you can run:
which case it will send it to stderr (this is just an example, and $ python echo.py --help
the normal echo command doesn’t have these flags). usage: echo.py [-h] [--stderr] echo
We’ll do this using the argparser module (new in Python echoing to stdout and stdin
2.7, so this won’t work if you’re using an older version). Using positional arguments:
this, you only have to specify what options you have, and the echo The stuff to print on screen
module will take care of parsing them and putting them in optional arguments:
variables so you can access them: -h, --help show this help message and exit
from __future__ import print_function --stderr print the stuff to stderr (otherwise print to stdout)
import argparse, sys You can fine tune argparser’s operation to almost any
parser = argparse.ArgumentParser(description=’echoing to stdout degree, and it has excellent documentation at: https://docs.
and stdin’) python.org/2/howto/argparse.html.
without corrupting the information going to stdout.
print(“\t”, num_lines,”\t”, num_words,”\t”, num_chars) For example, you might have used cat.py to output
As you can see, getting input from stdin is quite the contents of several files, but one of them doesn’t
straightforward. It’s read in in lines just like files are. exist. Using stderr, you still send the output of all the
These two tools can be linked together with: files to the next command in the chain, but also alert
python cat.py /usr/share/dict/words | python wc.py the user to the problem. Let’s take a look at how to
So far, we haven’t implemented any error checking. modify our cat command to deal with this:
So, if you try to cat a file that doesn’t exist, you get a from __future__ import print_function
Python exception: import sys, os.path
$python cat.py /nosuchfile | python wc.py for arg in sys.argv[1:]:
This might seem a little strange, because the error if not os.path.isfile(arg):
from the first Python command hasn’t been sent to print(“whoops, there appears to be a mistake. I can’t find”,
stdin of the second command. Instead it’s been arg, file=sys.stderr)
displayed on the screen. The reason for this is that else:
errors don’t go to stdout: instead, there’s a separate with open(arg) as file:
channel for them called standard error (stderr). This for line in file:
means that a program can send error messages print(line, end=””)
As you can see, all you have to do to print
something to stderr is include the parameter file=sys.
stderr in the print function, and you can print to it just
like you print to stdout.
Stderr doesn’t have to be printed on the screen
though; you can send it to a file instead. If you’re
running commands through some automated means
such as at or cron, it can be useful to collect any
errors. This is done with:
command 2> file
Anything a command sends to stdout, will be
printed on the screen (you could also pipe it into
further commands). Another option is to tell Bash to
send stderr to stdout. Doing this will combine stdout
and stderr into a single flow of text and pass it along
Even if one of the arguments to our cat program isn’t a to any future commands:
file, it will still handle the rest correctly. command1 2>&1 | command 2
www.linuxvoice.com 103
CODING ROBOCODE: ARTIFICIAL INTELLIGENCE WARFARE
ROBOCODE: ARTIFICIAL
TUTORIAL
INTELLIGENCE WARFARE
BEN EVERARD
A computer game that’s played by computers? Is this an open
invitation to Skynet or the future (or both)?
T
he idea of creating robotic warriors is as old as
WHY DO THIS? science fiction. However, how hard would they
• Satisfy your be to make? Let’s not worry about the physical
power cravings by things – that’s a problem for hardware engineers –
programming a robot and take a look at the software side of things.
army.
Robocode is an environment for tank-based
• Learn Java in a
well documented autonomous warfare. That means that rather than
environment. controlling the actions of your tank via a joypad or
• Give yourself a chance keyboard during the fight as you may in a regular
to win a Linux Voice computer game, you have to program it to behave in
T-shirt.
the way you want it to, then set it running. Before we
look at how to program the tanks, let’s first take a look
at the Robocode environment.
The main website is http://robocode.sourceforge. Let battle commence! Watching battles at normal speed
net, where you’ll find loads of useful information that helps you understand how the battles are fought, but
will come in handy if you decide to take on the cranking up the speed lets you test your robots quickly.
challenge. There’s also a download link that will
take you to a SourceForge page where you can grab can cd into this directory (by default it will be
the JAR file. To use this, you’ll need to have Java ~/robocode), and start the software with:
installed (we used OpenJDK 7, but other versions ./robocode.sh
The Robocode IDE is fine
may also work). Robocode comes with a range of sample robots, so
for simple robots, but if
you’re creating a more Once it’s downloaded, run: the first thing is to run a few battles to see how it
complicated warrior, you java -jar robocode-1.9.2.3-setup.jar works, and what tactics are effective. Go to Battle >
may prefer to use a more This will pull down all the files you need, and create New to create a new battle. On the first tab, pick a few
fully-featured IDE. a directory for them to live in. Once it’s finished, you robots to fight it out (it doesn’t really matter which
ones; we find that about five is a good number of
competitors). The second tab allows you to change
the settings for the battle (number of rounds, size of
battlefield, etc). You can leave these as the defaults.
Press Start Battle to begin.
Know your robots
You should see that each robot uses different tactics
to attack the others. Some (like RamFire) are really
aggressive, while others (like Corners) are more
defensive. Essentially, there are two parts to a robot’s
strategy. It needs to avoid the shells from other tanks,
and it needs to hit other tanks with its shells.
Before we dive in and start writing our own robot,
let’s take a look at how a couple of others work.
Robocode has its own built-in IDE, which you can use
to create robots in Java. Got to Robot > Source Editor
to open it, then Open > Sample > RamFire.java to take
a look at how the RamFire robot works. It is (in slightly
abridged form):
public class RamFire extends Robot {
int turnDirection = 1;
public void run() {
104 www.linuxvoice.com
ROBOCODE: ARTIFICIAL INTELLIGENCE WARFARE CODING
while (true) {
turnRight(5 * turnDirection); Advanced tactics
}}
Robots vary in complexity from the simple (by energy drop tracking), you don’t know
(like the ones we’re looking at) to the mind- what direction it’s gone in, but you can
boggling complex. Fortunately, you don’t predict a range of directions, and work out
public void onScannedRobot(ScannedRobotEvent e) { have to start out from scratch when building the rough probability of each. These areas
if (e.getBearing() >= 0) { your robot. There’s lots of information on of probability ripple outwards like waves
turnDirection = 1;} tried and tested tactics on the Robocode wiki from a stone dropped in a lake. Wave
(http://robowiki.net/wiki/Main_Page). Here surfing is the process of getting in the
else {
are a few of our favourite tactics: place of the lowest probability on this
turnDirection = -1;} Energy drop tracking Robots can’t see wave. There’s more details at: http://
turnRight(e.getBearing()); when bullets are fired, but they can detect robowiki.net/wiki/Wave_Surfing_Tutorial
ahead(e.getDistance() + 5); the amount of energy other robots have. If Bullet Shielding The aim of bullet shielding
scan(); that energy drops suddenly, it’s usually is to protect your robot by shooting your
because the other robot has fired a bullet. opponents’ bullets out of the air. That’s
}
This can be useful to other tactics such as quite easy to say, but much harder to
wave surfing and bullet shielding. achieve in practice. See http://robowiki.
public void onHitRobot(HitRobotEvent e) { Wave surfing If you see a robot fire a bullet net/wiki/Bullet_Shielding for the maths.
if (e.getBearing() >= 0) {
turnDirection = 1;
} else { the RamFire robot itself. Now let’s take a look at a
turnDirection = -1; more cautious robot. TrackFire also continuously
} looks for enemies, but rather than ramming them, it
turnRight(e.getBearing()); just shoots at them:
fire(1); public class TrackFire extends Robot {
ahead(40); public void run() {
}} while (true) {
There are quite a few comments that we’ve turnGunRight(10);
removed for brevity. The first thing that surprised us }
was just how simple the code is. Robocode handles }
everything about the environment, so you only need to public void onScannedRobot(ScannedRobotEvent e) {
decide how your robot will react to the environment
and code the AI. double absoluteBearing = getHeading() + e.getBearing();
Standard robots extend the Robot class (there are double bearingFromGun = normalRelativeAngleDegrees(a
other classes such as AdvancedRobot you can use bsoluteBearing - getGunHeading());
as well), and then override the appropriate methods. In
the case of RamFire, there are only three methods.
Run is triggered at the start of the battle and is used
to define the tank’s default behaviour. In this case, if
nothing else happens to the robot, it will simply spin
around on the spot.
OnScannedRobot is triggered when the robot’s
scanner pics up another robot. Control of the radar
(which picks up other tanks when scanning) can be a
complex topic, but in simple terms, it will just look in
the general area the turret is facing. Because the tank
will continually spin until directed otherwise, it will
always be on the look out for other tanks. This
method simply points the tank at the scanned tank,
and head straight for them.
When the robot rams into its victim, onHitRobot()
will run. This fires the cannon at them (the code here
is simplified), and it will ram them again.
As you can see, controlling your robot is all about
understanding the Robocode API. This is fully There’s an ongoing
documented at http://robocode.sourceforge.net/ Robocode competition
at http://literumble.
docs/robocode. You don’t need to dive straight in and
appspot.com. If you think
read it all, but as you develop fighting robots, you’ll
your creation is up to
probably find yourself heading there more and more the challenge, you can
frequently. set it against the rest of
RamFire works by aggressively pursuing robots – a the world and see how it
tactic that can work, but can also incur damage for matches up.
www.linuxvoice.com 105
CODING ROBOCODE: ARTIFICIAL INTELLIGENCE WARFARE
building one. We decided to base ours on the
TrackFire robot, but give it a bit more motion and the
ability to run away.
To start with, then, we just need to update the parts
that identify the robot, so open the TrackFire robot in
the source editor if you haven’t already, and change
the public class line to:
public class LVTrackFire extends Robot {
Then go to File > Save As and save it under a new
name (it should suggest LVTrackFire.java, which is
fine). You now have a new robot. To make sure
everything’s gone properly, go to Compiler > Compile,
then (if there are no errors), go to the main Robocode
window and create a new battle. You should find your
robot under Sample.
The robot wiki is an invaluable source of information and inspiration for all things
Robocode. http://robowiki.net/wiki/Main_Page
Added intelligence
Of course, at this stage, the AI for LVTrackFire is
exactly the same as TrackFire, so let’s now go back
if (Math.abs(bearingFromGun) <= 3) { and add some more intelligence to it.
turnGunRight(bearingFromGun); The biggest problem TrackFire has is that it stays
if (getGunHeat() == 0) { still. We’ll add a bit of movement logic to our robot in a
fire(Math.min(3 - Math.abs(bearingFromGun), few ways:
getEnergy() - .1)); Under normal operation, it will move forward slowly.
} This will help it avoid fire from robots far away.
} If it’s hit, it will quickly get out of the way. This will
else { hopefully move it out of the scan of the robot that’s
turnGunRight(bearingFromGun); just hit it.
} If it hits a wall, it will get away. This stops it being
pinned in by RamFire.
if (bearingFromGun == 0) { We can add this logic in stages. Firstly, we’ll make it
scan(); move forward under normal operation. To do this, just
} add one line to the run method as follows:
} public void run() {
} while (true) {
As you can see, this is quite simple. Rather than turnGunRight(10);
spinning the robot, it just turns the gun, and rather ahead(10);
than speeding off towards its victim, it just points the }
cannon at them and fires.
There is a little complication with firing because you
(as the programmer) can decide how much power to Famous fighters
give the gun. The more power (the parameter to the
The robots that come with Robocode are enough to keep
fire command), the more damage it potentially does
you interested while you get started, but if you really want
your enemy, but the more it also heats up your gun. If to test your skills, you may want to test yourself against
your gun overheats, you can’t fire until it cools down. some more powerful opposition. Alternatively, you may just
A good general tactic is to fire with more power the want to watch some masterful killing machines at work.
more confident you are of hitting your enemy. In this Whichever is your motive, you can find more robots online
at http://robowiki.net/wiki/Category:Bots. A few of our
example, we’ll fire if the angle between where the gun
favourites are:
is pointing, and the tank we’re trying to hit is less than DrussGT (http://minifly.rchomepage.com/robocode/
three degrees. However, the smaller the angle is, the jk.mega.DrussGT_2.0.6.jar)
more power we’ll give the shot. This isn’t necessarily Diamond (www.dijitari.com/void/robocode/voidious.
optimal because it doesn’t attempt to work out Diamond_1.7.11.jar)
Demonic Rage (http://sites.google.com/site/
whether the target is moving.
justinsitehere/file-cabinet/justin.DemonicRage_3.4.jar)
If you watch TrackFire fight a few battles, you’ll If you want to see some top Robocode action, put
probably notice that the biggest problem it has is that Demonic Rage in a ring with DrussGT and Diamond to see
it can be a sitting duck. Once it turns up in an enemy’s which comes out top. If you can build a robot that can
scan, it is usually destroyed fairly quickly because it compete with these three, you’ve done very, very well.
These are all open source, so you can poke around in
doesn’t get away.
their insides and see what makes them tick. Perhaps you’ll
Now you’ve seen a few robots in operation, and find something to inspire your own battle bot.
seen how a couple are written, it’s time to start
106 www.linuxvoice.com
ROBOCODE: ARTIFICIAL INTELLIGENCE WARFARE CODING
}
This keeps the gun spinning as before (and so
keeps it scanning for other robots), but makes it move
as well.
The next bit of code we want is to make the robot
run away whenever it’s hit. Again, we don’t really care
where it runs away to, we just want it get away from
its current location. In this case, we could just move
forwards a certain distance. This is what the first
iteration of our robot did, but in a crowded battlefield,
we found that this doesn’t work very well. Our tank
often got stuck when it hit other tanks and didn’t run
away successfully, so instead, we made it move
forwards, turn, then move forwards again. This is
done with the following method:
public void onHitByBullet(HitByBulletEvent e) {
for(int x = 0; x < 2; x++) {
ahead(150);
turnRight(50);
}
}
IBM’s Developer Works has
The final bit of movement (to keep the robot away if (Math.abs(bearingFromGun) <= 3) {
a series on learning Java
from walls) is done with: Reducing the value 3 will mean the gun will wait
with Robocode at http://
public void onHitWall(HitWallEvent e) { until it has pointed more accurately before it fires. This robocode.sourceforge.net/
for(int x = 0; x < 3; x++) { will reduce the rate of fire, but increase the number of developerWorks.php. It’s a
ahead(100); bullets that reach the target (since the target could be little dated now, but should
turnRight(50); moving, it’s not easy to aim accurately). still work.
} You can also adjust the firepower. None of these
} change the fundamental operation of the robot, but by
This is the mechanics robot complete. We were tuning the parameters, you can make your killing
happy with TrackFire’s firing, so we didn’t change this. machine more effective.
You can compile it and pit it against other robots in Our simple robot isn’t the most devastating
battle and see how it fares. opponent, but hopefully it will have whetted your
Although it’s all done, there are still some bits you appetite to build your own AI tank. It should also prove
can tweak to make the robot more effective. a fairly easy starting point to surpass as you add more
The speed at which our robot moves is governed by features, you should quickly be able to superseded
the number in ahead(10) in the run method. By this primitive AI.
increasing or decreasing this number, you can make it
faster or slower. You can also adjust the accuracy of Ben Everard is the best-selling author of Learning Python With
Raspberry Pi. He hacks robots for fun.
the aiming in the line:
COMPETITION
We’re going to run a digital Battle Royale.
There are lots of open source robots available, so for(int x = 0; x < 3; x++) { Voice winner’s T-shirt. All the
we’re going to make our challenge a bit different to ahead(100); battles will take place on a
most Robocode competitions to discourage the use turnRight(50);} 1000x800 battlefield with a
of these open source bots. Obviously, the best tactics will depend on how gun cooling rate of 0.1, an
Firstly, your tank must extend the Robot class, the battles are structured. In our war, the battle will inactivity time of 450 and a sentry size of 450.
not AdvancedRobot or any of the others available take place in a series of heats. Each heat will have All robots must be licensed under a OSI-
in Robocode. Second, the whole robot must come in six robots (if the number of robots isn’t divisible by approved open source licence (we recommend
at under 70 lines of Java. A line (for the purposes of six, sample robots will be included to bulk up the the GPL v3). The robot doesn’t have to be entirely
this challenge) is a statement ended by a semicolon numbers). Each heat will be 100 rounds, and the your own work: borrowing chunks of code from
(not including the separate parts of a for loop), or top three will progress to the next round. We’ll go other openly licensed robots is allowed, as is
a statement that starts a new code block (such through as many rounds as necessary to whittle the using existing robots as a starting point for your
as if, else, while etc). Parentheses may be put at field down to six robots for the grand final. This will development, although you obviously must adhere
the beginning or end of any line and don’t need a take place over 200 rounds and the winner of this to the terms of the licence of any code you borrow.
separate line. Therefore, the shortest the following will be crowned Linux Voice Robocode champion. Please email your robot’s source code to
code can be is three lines: The winner will, of course, get an exclusive Linux ben@linuxvoice.com by 20 December 2014.
www.linuxvoice.com 107
MASTERCLASS DVD-VIDEO TOOLS
MASTERCLASS
Without music, life would be a mistake. Join us as we
BEN EVERARD celebrate the new UK legal status of ripping your own CDs.
DVD-VIDEO: RIP AND BURN...
Now that you can legally copy DVDs, we show you how.
O
n 1 October, the UK’s copyright law caught up
JOHN LANE with the real world. You can now legally make
personal copies of your favourite ebooks,
music and videos that you own. So, without further This is just a screenshot of twitter.
ado, this month’s Masterclass will have you making
backups of your favourite DVDs in no time. We’ll
explain the structure of a DVD and show you how to
make your own so that you can now make that movie The UK Government now communicates changes in the
you’ve always wanted to. law of the land via the proprietary medium of Twitter. If it
There are two ways to copy a DVD. The first is to is Tweeted, it must be official.
create an ISO image of the whole disc – an exact
copy. Most media players will play images just like the most basic method – it copies the raw data from the
real thing and you can burn them onto blank media to disc’s block device into an image file.
make an exact copy. The other way is to extract the The following commands are equivalent, as they
contents of the DVD’s filesystem by recursively copy the entire disc:
copying its root directory. Again, most media players $ dd if=/dev/sr0 of=mydvd.iso
will play a directory tree copied from a DVD. $ cp /dev/sr0 mydvd.iso
Before you start copying, make sure you have It’s possible for these methods to receive a few null
sufficient free storage. A typical DVD weighs in at blocks at the end of the stream. They won’t affect the
around 7GB – you can see the actual size of a disc image but, for an exact block-perfect copy, you can try
with the isosize command: these instead:
$ isosize /dev/sr0 $ dd if=/dev/sr0 of=mydvd.iso bs=2048 count=$(isosize -d 2048
6654584832 /dev/sr0)
This outputs the raw size of the disc’s filesystem in $ head -c $(isosize /dev/sr0) </dev/sr0 >mydvd.iso
bytes (our optical drive is /dev/sr0). These use isosize to obtain the exact size of the
If you just want to make an ISO image, you may be original and then copy that amount of space (the
able do it with the dd or cp commands. This is the block size of a DVD is 2048 bytes). A md5sum hash
of the original disc and images produced this way
Install the packages should match.
Some of the tools that we will use are included in the base Authoring
packages of most distros (for example, things like dd and
If you encounter errors then you might be able to
isosize, which we use to make ISO images). You’ll need
some other tools to go beyond, however. overcome them by adding conv=noerror,sync to the
lsdvd displays the contents of a DVD; it’s a quick way to end of the dd command. These arguments make the
identify the main title on a disc, because this is usually dd command continue after errors (noerror) and
the longest track. NUL-pad the error blocks (sync) to preserve the image
vobcopy copies the contents of a DVD as files and
size. Both these methods of using the dd command
directories.
libdvdcss decrypts titles that use the Content Scramble provide a disc image suitable for playback on many
System (CSS). players, such as VLC; they provide a true backup of the
ffmpeg is used to transcode video files into the format whole disc, complete with any encryption and copy
required by DVD-Video. protection they may have.
cdrtools provides the tools we need to write ISO images
If you want to modify your copy, perhaps by
to disc.
extracting only the main title to save space or by
108 www.linuxvoice.com
DVD-VIDEO TOOLS MASTERCLASS
Intentionally bad sectors
VIDEO_TS
The DVD copier’s nemesis is the intentional ignored; they’re intentional and contain no
bad sector. These are sectors that have data so we don’t care about them. The block
incorrect CRC checksums, and they are used size of a DVD is 2048 bytes.
VIDEO_TS.INFO VTS_01_0.IFO VTS_02_0.IFO as a crude copy protection on some If the image is still unplayable, extract it
commercially produced discs. Most with vobcopy or dvdbackup and play that
standalone players don’t encounter the instead. If you still want an ISO, perhaps to
VIDEO_TS.BUP VTS_01_0.BUP VTS_02_0.BUP errors because they are avoided by the disc write to another disc, you could use mkisofs
indexes (the IFO files) they follow but they to make one from the extracted directories.
are hit by attempts to image the disc. An alternative method is to locate the
VIDEO_TS.VOB VTS_01_0.VOB VTS_02_0.VOB
There are several such schemes, with main title and stream it into a file:
names like ARccOS, XProtect and RipGuard. $ lsdvd /dev/sr0
VTS_01_1.IFO VTS_02_1.IFO If you encounter such a disc, you should be longest track is 4
able to make an ISO from it with the GNU $ mplayer dvdnav://4 -dvd-device //dev/sr0
ddrescue tool, like this: -dumpstream -dumpfile main_title.mpg
VTS_01_2.BUP $ ddrescue -n -b 2048 /dev/sr0 mydvd.iso ddrescue may also help you rip a
The -n parameter causes bad blocks to be scratched disc.
VTS_01_3.VOB
x.bup are identical). The third kind of file is the VOB
Each title on a DVD has files collectively called a Title Set; (Video Object), and these contain the actual media:
there can be up to 99 title sets on one disc. This example video, audio and subtitles. They’re basically MPEG-2
has two; the first is divided into four VOB files and the Program Stream files with DVD-specific limitations.
second one is divided into two. Any player that can play MPEG can play unmodified
VOB files. Because they can’t be larger than 1GB,
transcoding for playback on other devices, then you’ll longer titles are split into multiple files. You can,
need to read the data files from the disk and work with however, use cat to join them:
those instead. The long-standing tool of choice for $ cat mydvd/VIDEO_TS/VTS_01_*.VOB > title.mpg PRO TIP
this is the vobcopy command, which requires that you The files follow a strict naming convention: the You can use cp on its own
mount the DVD first: VIDEO_TS files are for the Video Manager and contain to copy unencrypted files
$ sudo mount /dev/sr0 /mnt the control and playback information for the disc, from a mounted DVD.
$ vobcopy --mirror /mnt referring to title sets which are the VTS_nn_n files on
The DVD will be extracted to a new directory the disc. Once you understand the format, you can
created inside the current directory, whose name will make your own DVDs by creating the appropriate files.
be determined by the titling on the DVD (usually the
name of the programme on the disc). If the files are Authoring
encrypted and the appropriate libraries are installed Taking regular video files and making a DVD from
then vobcopy will decrypt them first so that it can them is called authoring. Your source material may be
copy them and the resulting copies will be free from in various formats and will probably need to be
encryption. transcoded first; one suitable tool is ffmpeg:
$ ffmpeg -i my_video.mp4 -target pal-dvd my_dvd_video.mpg
A look inside The simplest authoring just takes your video file PRO TIP
If you look at an extracted DVD-Video disc you will see and packages it into a DVD-Video directory structure dvd+rw-mediainfo /dev/
that there is a directory named VIDEO_TS at its root suitable for the PAL video system used in the UK: sr0 shows useful
information about the
(there may also be an AUDIO_TS directory, which is $ export VIDEO_FORMAT=PAL disc.
for DVD-Audio discs and is normally empty on a $ dvdauthor -d my_dvd -t my_dvd_video.mpg
DVD-Video disc). $ dvdauthor -d my_dvd -T
The VIDEO_TS directory contains three kinds of The last command writes the DVD table of contents
files: IFO (information) files tell the player how to and completes a basic example that will play a single
navigate the disc and have BUP backups (x.ifo and title when the disc is inserted. You can create an XML
configuration file to define chapter marks and multiple
titles or add menu systems - read the documentation
tccat: another way to extract a title
at http://dvdauthor.sourceforge.net to learn more.
You can use cat to extract a DVD title, but the resulting Before you can give that holiday video to your gran,
MPEG header will have incorrect duration data, which can you need to make an ISO image and put it onto a disc:
cause confusion in some players. The transcode package
includes a utility called tccat that offers another way to $ mkisofs -dvd-video -o my_dvd.iso my_dvd
achieve a similar result direct from a disc or image: $ cdrecord -dao dev=/dev/sr0 my_dvd.iso
$ tccat -i /dev/sr0 -T1,-1 > output.mpg $ cdrecord -fix dev=/dev/sr0
The -T option specifies the track to extract. The format is Fixating the disc is the final step and makes it ready
-T<track>,<chapters> and specifying a chapter value of -1 for use in standalone players. If it doesn’t happen
selects the whole track.
automatically the last command will do it.
www.linuxvoice.com 109
MASTERCLASS DVD-VIDEO TOOLS
DVD-VIDEO: RIP AND BURN
The GUI way to read and write your video DVDs.
Y
ou are somewhat spoilt for choice if you prefer
JOHN LANE to use a desktop application to read and write
DVD-Video media. If you’re looking for ease of
use the current favourite is Handbrake, an open-
source, GPL-licensed but Apple-flavoured video
transcoder. If all you want to do is extract content
from a DVD to watch on your phone, tablet, desktop or
smart television then look no further than your distro’s
repository.
Handbrake comes in command line and GTK
desktop versions; the executable for the latter is called
ghb. When you start it, the main screen is displayed
and is where you select source material, desired
encodings and other settings. Handbrake at work: the Start button changes to Stop
You can choose from almost any video file format while it’s working. It takes around 30 minutes to
PRO TIP supported by libavformat and libavcodec. The output transcode a feature film.
Handbrake writes MP4 file formats are limited to MKV and MP4, but these
files with a .m4v
extension so QuickTime
can contain various video encodings including H.264, Start. That’s all there is to it. Because Handbrake
and Qt 4 applications can MPEG-4 and MPEG-2 along with the usual audio copies and also transcodes, or converts from one
play them properly. There encodings that go with them. For use with most format to another, it takes longer than a simple copy
is no internal difference.
modern devices, it probably has your needs covered. would, but it works and gets the job done without a
To make it even easier for you, the right-hand side of great deal of fuss.
the main window displays presets, mostly for Apple
and Android phones and tablets, but there is also the Make your own DVD
default preset (Normal) and a general-purpose preset One thing that Handbrake doesn’t do is DVD authoring
for H.264 video (High Profile), with all the bells and – this is the preparation of video in the required
PRO TIP whistles. You can also add, modify and remove format and creating the menu system used to
Advanced users can presets, whether they’re built-in or your own. navigate the disc. There are quite a few tools that
tweak Handbrake’s x264
encoder parameters; they Copying a DVD is easy: place it in your drive and purport to offer these capabilities. One of them is
are documented at press the Source button to select it (this is also how called Bombono DVD and should be in your distro’s
https://trac.handbrake.fr/ you’d choose material on your hard drive). Once repository. Its GTK user interface is straightforward,
wiki/x264Options.
selected, the disc is scanned and the title list is having three main tabs that are used to select the
populated. Handbrake attempts to select the main title source material, build a menu system and, finally,
for you, and you can use the Title drop-down menu to write the disc. The writing stage can include writing
select any title. You can select part of the title by
chapter numbers, time in seconds or frames. Choose
your desired preset, set the destination and press Support options
Handbrake benefits from decent documentation and
support resources. There’s a user guide, forums and you
can head over to #handbrake on Freenode IRC and
https://handbrake.fr.
Bombono’s video timeline lets you move through a title and set chapter marks.
110 www.linuxvoice.com
DVD-VIDEO TOOLS MASTERCLASS
the DVD directory tree, creating the disc image (ISO
file) and burning the image to a disc.
The first stage is where you choose your content;
you don’t need to worry about its format because it
will be transcoded into the required MPEG-2 Program
Stream format that DVD-Video needs. You also don’t
need to worry about its size, because you can adjust
its bitrate to fit on the destination media. To add
media, you can either drag it on to the left-hand Media
List panel or use its Add Media Files button to select
them from a pop-up list. You can re-order selected
titles by dragging and renaming them (although this
has nothing to do with the DVD-specific names used
on the disc).
You can right-click on a title to choose what should
happen when it ends; the default action is to return to
the menu. You also right-click and use ‘Adjust Bitrate
To Fit To Disc’ to make sure your content will fit.
Menus
The next stage is to prepare menus. You can set a
background image and write text labels or drag and
drop chapters to produce a set of thumbnails that
play from those points in the title, and there are basic
align and distribute tools to help you lay them out
neatly. Menu creation is something you could quite
easily get carried away with, but can yield good results
to give your disc a polished look and feel.
Writing is the final stage and uses the command-
line dvdauthor utility underneath. You have to select a
working directory and it’s a good idea to create a new, You can create menus with DeVeDe but the options are limited – there are no dragging
empty, one for this. You can choose whether to only elements here and no submenus, but it is quick and easy.
create the DVD folder – the directories and files that
will go on the disc – to create an image or burn onto a (no thumbnails here) and you can choose where they
disc. If your content needs to be transcoded, the appear: at the top, middle or bottom and either on the
process will take longer. left, right or in the centre. You can also place an overall
Another popular tool that performs similar tasks is title across the top of the menu screen and select a
DeVeDe: you select your content, create menus and soundtrack and a background image (this needs to be
launch it. A little while later, your choice of a disc prepared to the correct aspect ratio beforehand or will
structure or ISO pops out. There’s no option to burn appear distorted). A preview window shows you what
that to a disc, so you’ll need to use something else for your menu will look like.
that task. Once your disc image is written, you can preview it
The menu options are more limited than Bombono’s: in a player such as VLC to make sure it’s OK before PRO TIP
you can only have one menu and the layout options using a separate burning tool to write it to a disc. Handbrake’s preset
are much more primitive. It displays each title as text parameters are described
Spoilt for choice; spoiled by cruft at https://trac.handbrake.
fr/wiki/BuiltInPresets.
A few alternatives If you search your repositories for graphical GUI tools,
you’ll find options of varying quality, many of which
MakeMKV is dedicated to ripping DVD-Video to Matroska are either abandonware that will present problems as
MKV containers.
soon as you try to install them, or feature-poor,
PGCEdit is a DVD IFO and menu editor designed to allow
the modification of the navigation commands and knocked-together efforts that fail to meet their
parameters of an already authored DVD structure. objectives. This is one area of open source software
AcidRip, a GTK wrapper for the mencoder command, is where there is a significant amount of cruft.
feature-rich but one for the more advanced user. That said, the ones that we’ve used here work well
Brasero is a beginner-level tool that is a standard part of
and do what they were designed to do. Have faith
the Gnome desktop.
K3b is the KDE application for ripping and burning media. – the package manager will provide.
And then there’s VLC, which can do just about anything.
But that flexibility cost is met by complexity that may be John Lane provides technical solutions to business
too much for the casual user taking a backup of the problems. He has yet to find something that Linux can’t
occasional DVD. solve.
www.linuxvoice.com 111
DVDPAGES
Don’t fall behind – get the latest Linux goodness today!
DVD 010
SAY HELLO TO THE UTOPIC UNICORN
Ubuntu has had its ups and downs installing Linux, we can highly our very first issue under the
over the years, but it remains one recommend Ubuntu. Creative Commons (CC-BY-SA).
of the most popular distros of all, But it’s not just for newbies: This means you’re free to share it
and is the entry point into Linux I personally run Xubuntu as my and create new content based on
for many people. It’s polished, it’s main production distro. It has a it – just give us credit for making
built on a solid foundation (Debian) great out-of-the-box experience, it in the first place! See index.html
and there are huge support a super fast and slick desktop, on the DVD for more information.
communities on the internet in good hardware detection and huge Happy Linuxing!
case you have problems. If you’ve package repositories.
picked up this magazine for the On another note, as this is Linux Mike Saunders, Disc Editor
first time and you’re thinking about Voice issue 10, we’re giving away mike@linuxvoice.com
Distro powerpack
Ubuntu 14.10
Full 64-bit version, directly bootable from the disc
Y
es, it’s that time of year again: The version of Ubuntu 14.10 on our DVD
another Ubuntu release is here. This is 64-bit, and you’ll need at least 1.5GB
one isn’t particularly radical in terms of RAM and 10GB of hard drive space. If
of changes, but that’s fine with us; it’s not you’ve never installed Linux before and you
necessary to have a giant upheaval every six only have Windows on your drive, you can
months. Ubuntu 14.10 is an incremental and choose to shrink the Windows chunk of the
evolutionary release, with a handful of new drive (its partition) during the installation, to
features backed up by package updates, make room for Linux. Then you’ll be able to
bugfixes and refinements. If you’re running a choose your operating system when you
previous release, it’s worth the upgrade just boot your PC. Before installing, though, it’s a
to get the latest packages – or if you’re a good idea to back up important data!
newbie in the Linux world, it’s a great way to If you’re looking for something with
get started. You can find out more about the lower system requirements, or you want mentioned below. And if you get stuck at
latest release in our review on page 48, so to squeeze extra performance out of your all, consult the friendly Ubuntu community
here we’ll focus on installation. PC, try one of the other Ubuntu variants online at www.askubuntu.com.
Xubuntu, Kubuntu, Lubuntu
And there’s more! Ubuntu re-spins galore
This month’s DVD is a quad-booter, so along environment, generally considered the
with the regular Ubuntu version, it can also most flexible and featureful in the Free
boot Kubuntu, Xubuntu and Lubuntu. Just Software world. Xubuntu (also 64-bit) uses
choose the one you want from the Grub menu the faster and lighter Xfce desktop. And
when you boot the disc, and you’ll soon arrive for older machines, we’ve added Lubuntu
at your choice of desktop. (32-bit) which only needs 512MB of RAM,
Kubuntu (64-bit) uses the KDE desktop and is bundled with various memory-friendly Lubuntu (www.lubuntu.net) is great for
instead of Unity – this is a very mature desktop applications. breathing new life into old PCs.
112 www.linuxvoice.com
DVDPAGES
How it works: Installing Ubuntu 14.10 from the DVD
Boot your PC from the DVD, and you should see this menu. (If not, you may After choosing the Ubuntu flavour you want, you’ll arrive at the desktop.
1 2
need to change the boot order in your BIOS – see your PC’s manual.) This is live mode, so you can explore the software before installing.
Double-click the installer icon on the desktop and the installer will pop up Next, partition (divide up) your hard drive: dedicate it all to Ubuntu, share it
3 4
and ask if you want to download updates and third-party add-ons. with another Linux distro or Windows or something else (custom setups).
Advanced users: if you do custom partitioning, you’ll need at least a root (/) You’ll then be asked to set your keyboard layout and create a user account.
5 6
partition along with swap (twice your RAM, but no bigger than 4GB). You can encrypt your personal files, but it has a performance impact.
The Ubuntu files will be copied over to your hard drive, so grab a cup of tea And you’re done! Once the installation is complete, your system will reboot,
7 8
and watch the slideshow highlighting some of the distro’s features. eject the DVD, and start Ubuntu from your hard drive. Enjoy!
www.linuxvoice.com 113
/DEV/RANDOM/
Final thoughts, musings and reflections
Nick Veitch
was the original editor
of Linux Format, a
role he played until he Club Mate, the A Yoga 13, where I boot
got bored and went essential hacker the most recent Systemd
to work at Canonical beverage. versions on, and hence
instead. Splitter! might break frequently.
It’s running Mutt (what
else!).
Connected to a fall-
I
back desktop machine,
t has been 10 years since the first version of which runs slightly less
current Systemd and
Ubuntu launched to largely unsuspecting Fedora versions.
masses. It was brown. It was easy to install.
It changed the history of Linux distros (whether
or not you ever used it) and 10 years later on is Bauhaus (Mart Stam). What Contains memory cards,
A Nexus 5. Bauhaus did for architecture and and more memory cards
more or less the most popular version of Linux in design might actually be a good are lying next to the big
the known universe. There has been controversy. influence when hacking ;-) screen, because I need
No doubt there will continue to be so. The world to pull my pictures from
my India trip off them.
rarely changes without it. But even detractors
would have to admit that in the primary mission
of making a “Linux for human beings” it has been
tremendously successful.
A lot of other things have changed in 10 years.
Who would have thought you would ever see a My Linux Setup Lennart Poettering
Microsoft CEO delivering a keynote in front of a
huge screen proclaiming “Microsoft ♥ Linux”?
The creator of PulseAudio and Systemd gives us a
And yet, it has come to pass (http://goo.gl/ glimpse of his coding den.
dpJloJ). This is largely because of Azure,
Microsoft’s cloud platform, which has to be What version of Linux are you which I stayed with for a long time.
Linux-friendly because various flavours of Linux using at the moment? What Free Software can’t you
(notably Ubuntu) are the most popular images I have a laptop with current Fedora live without?
used in the cloud (and about 20% of Azure). Rawhide, which I use for day-to-day Uh, oh. To be honest, from time to
A lot of other things haven’t changed. It is still hacking. I also have a desktop with stable time when I travel I live without any
difficult to find a choice of laptop with Linux Fedora 20, so that I always have a computer or software for a month, and I
pre-installed, and even if you decide to install it machine I can email from. really enjoy it… That said, if you press me
yourself, some shop staff often seem, erm, hard I’d say Emacs, of course!
confused about what that entails (http://goo.gl/ What was the first Linux setup
Hnh4JO). But wait, things have changed here you ever used? What do other people love but
too, as Currys reaffirmed that wasn’t their official I got Slackware from a friend, some you can get on without?
policy (http://goo.gl/U0DGCb). time in 1996, when I was 16. It was Hmm, good question. LibreOffice
Who knows what may change in the next ten awful, I really didn’t understand a thing I Impress, maybe? I do all my slides
years? By the time we get around to Omnipotent was doing back then, so after two weeks I with Latex Beamer!
Owl maybe (if Systemd hasn’t morphed into deleted Slackware again and moved back
Skynet and destroyed humanity) people will be to Windows. Is there a piece of proprietary
happy with their desktop environment, all A year and a half later I then bought a software you wish were free and
hardware will ship with Linux support and Linux shrink-wrapped box of Red Hat 5.0, open source?
Voice will be beamed directly to your neurons. I together with a friend. I still didn’t get it The Coverity static analyzer is really
bet Berlin still won’t have settled on a standard really, but I found it interesting enough to the only thing that comes to mind
for office software though. stick with it, and then switched to Debian here for me!
114 www.linuxvoice.com
Systemd Cheat Sheet
CC-BY-SA Ivan Yossi)