FBB::SyslogBuf - A streambuf object inserting syslog messages
#include <bobcat/syslogbuf>
Linking option: -lbobcat
Addresses of FBB::SyslogBuf objects can be passed as
std::streambuf addresses to std::ostream objects to write
messages to the syslog daemon using stream facilities.
Multiple separate insertions can be used to create a single syslog
message: the message is only sent to the syslog daemon after receiving a
flush command (e.g., after inserting std::flush or
std::endl). Non-printable characters (like ’\n’)
show up in the syslog message as octal values, preceded by # (e.g.,
#012 for ’\n’). The newline normally inserted by
std::endl is ignored: SyslogStream objects interpret
std::endl like std::flush.
One series of insertions may contain multiple std::endl or
std::flush manipulators. At each of these manipulators a new message
is sent to the syslog daemon, containing all info that has so far been
buffered. After sending a message to the syslog daemon, the
SyslogStream’s internal buffer is cleared.
FBB
All constructors, members, operators and manipulators, mentioned in this
man-page, are defined in the namespace FBB.
FBB::EoiBuf and thus from std::streambuf
The following enumerations are defined in the namespace
FBB:
Priority:
The values of this enumeration match the corresponding priority
LOG_xxx values used with syslog(3):
- o
- EMERG:
system is unusable;
- o
- ALERT:
action must be taken immediately;
- o
- CRIT:
critical conditions;
- o
- ERR:
error conditions;
- o
- WARNING:
warning conditions;
- o
- NOTICE:
normal, but significant, condition;
- o
- INFO:
informational message;
- o
- DEBUG:
debug-level message;
PriorityType:
This enumeration has two values fine-tuning the type of messages
that are actually processed by the syslog daemon:
- o
- SINGLE:
Only messages of the priority specified at the setMask call are
processed by the syslog daemon;
- o
- UPTO:
Messages of priority EMERG up to the the priority specified at the
setMask call are processed by the syslog daemon; By default, the
syslog daemon processes all messages it receives.
Facility:
The values of this enumeration match the corresponding facility
LOG_xxx values used with syslog(3):
- o
- AUTHPRIV:
security/authorization messages (private)
- o
- CRON:
clock daemon (cron and at)
- o
- DAEMON:
other system daemons
- o
- KERN:
kernel messages
- o
- LOCAL0:
reserved for local use. LOCAL1 through LOCAL7 are available as
well.
- o
- LPR:
line printer subsystem
- o
- MAIL:
mail subsystem
- o
- NEWS:
USENET news subsystem
- o
- SYSLOGBUF:
messages generated internally by syslogbufd
- o
- USER:
generic user-level messages
- o
- UUCP:
UUCP subsystem
- o
- SyslogBuf(string const &ident = "", FBB::Priority
priority = FBB::NOTICE, FBB::Facility facility = FBB::USER,
int option = 0):
The ident parameter is usually the name of the program. Its content
are prepended to syslog messages.
- The priority parameter determines the default importance of the
message sent to the syslog daemon. By default messages are sent to the
syslog daemon with priority FBB::NOTICE. Syslog messages may be
given different priority by inserting a SyslogStream(3bobcat)
manipulator. The priority set at construction time may also be modified
using the setPriority and setDefaultPriority members.
- Which messages actually appear in log facilities is not determined by the
messages’ priorities, but by syslog’s log mask. The
log mask can be set by the static member setMask (see below).
- The facility parameter determines the type of program doing the
logging. By default FBB::USER is used.
- The option parameter may be used to specify various options (use
the binary `bitor’ (`|’) operator to combine
options):
- LOG_CONS: write directly to system console if there is an error
while sending to system logger
LOG_NDELAY: open the connection immediately (normally, the con-
nection is opened when the first message is logged)
LOG_PERROR: print to stderr as well
LOG__PID: include PID with each message
- By default no options are used.
Copy and move constructors (and assignment operators) are not
available.
All members of std::streambuf are available, as
FBB::SyslogBuf inherits from this class.
- o
- Priority defaultPriority() const:
Returns the current default priority. I.e., the priority that will be used
for the messages after inserting endl or flush.
- o
- void eoi():
If the SyslogStream’s internal buffer is not empty it is
flushed to the syslog daemon. Thereafer closelog(3) is called.
Instead of using this member the eoi manipulator can also be
used.
- o
- Priority priority() const:
Returns the next priority. I.e., the priority that will be used for the next
message that is sent to the syslog daemon.
- o
- void reset(string const &ident, FBB::Priority priority =
FBB::NOTICE, FBB::Facility facility = FBB::USER, int option
= 0):
Redefines the current identifier, priority, facility and options that are
used when sending messages to the syslog daemon. If the
SyslogStream’s internal buffer is not empty it is first
flushed to the syslog daemon using the identifier, priority and options
that were active just before calling open.
- o
- Priority setDefaultPriority(Priority priority):
Changes the default priority of the next message that is sent to the syslog
daemon after inserting std::eoln or std::flush. The
previously active default priority is returned.
- o
- Priority setPriority(Priority priority):
Changes the priority for the next message that is sent to the syslog daemon
after inserting std::eoln or std::flush. Subsequent messages
will again use the default priority. The previously active priority
setting is returned.
- o
- FBB::eoi:
The eoi manipulator can be inserted into the ostream instead
of calling the SyslogBuf::end member. It performs the same actions
as the eoi member. If inserted into a plain std::ostream
nothing happens.
See also syslogstream(3bobcat)
#include <iostream>
#include <bobcat/syslogstream>
using namespace std;
using namespace FBB;
int main(int argc, char **argv)
{
ostream sls(new SyslogBuf(argv[0]));
sls << SyslogStream::debug << "Hello world" << flush <<
SyslogStream::strerrno << endl;
}
bobcat/syslogbuf - defines the class interface
The constructor’s option parameter is an int.
Because of this, int values rather than enumeration values are passed
to the constructor. It is the responsibility of the programmer to pass
defined option values only.
- o
- https://fbb-git.gitlab.io/bobcat/: gitlab project page;
- o
- bobcat_6.02.02-x.dsc: detached signature;
- o
- bobcat_6.02.02-x.tar.gz: source archive;
- o
- bobcat_6.02.02-x_i386.changes: change log;
- o
- libbobcat1_6.02.02-x_*.deb: debian package containing the
libraries;
- o
- libbobcat1-dev_6.02.02-x_*.deb: debian package containing the
libraries, headers and manual pages;
Bobcat is an acronym of `Brokken’s Own Base Classes And
Templates’.
This is free software, distributed under the terms of the GNU
General Public License (GPL).
Frank B. Brokken (f.b.brokken@rug.nl).