DOKK / manpages / debian 12 / inn2 / docheckgroups.8.en
DOCHECKGROUPS(8) InterNetNews Documentation DOCHECKGROUPS(8)

docheckgroups - Process checkgroups and output a list of changes

docheckgroups [-u] [include-pattern [exclude-pattern]]

docheckgroups is usually run by controlchan in order to process checkgroups control messages. It reads a list of newsgroups along with their descriptions on its standard input. That list should be formatted like the newsgroups(5) file: each line contains the name of a newsgroup followed by one or more tabulations and its description.

docheckgroups will only check the presence of newsgroups which match include-pattern (an egrep expression like "^comp\..*$" for newsgroups starting with "comp.") and which do not match exclude-pattern (also an egrep expression) except for newsgroups mentioned in the pathetc/localgroups file. This file is also formatted like the newsgroups(5) file and should contain local newsgroups which would otherwise be mentioned for removal. There is no need to put local newsgroups of hierarchies for which no checkgroups control messages are sent, unless you manually process checkgroups texts for them. Lines beginning with a hash sign ("#") are not taken into account in this file. All the newsgroups and descriptions mentioned in pathetc/localgroups are appended to the processed checkgroups.

If exclude-pattern is given, include-pattern should also be given before (you can use an empty string ("") if you want to include all the newsgroups). Be that as it may, docheckgroups will only check newsgroups in the top-level hierarchies which are present in the checkgroups.

Then, docheckgroups checks the active and newsgroups files and displays on its standard output a list of changes, if any. It does not change anything by default; it only points out what should be changed:

  • Newsgroups which should be removed (they are in the active file but not in the checkgroups) and the relevant ctlinnd commands to achieve that;
  • Newsgroups which should be added (they are not in the active file but in the checkgroups) and the relevant ctlinnd commands to achieve that;
  • Newsgroups which are incorrectly marked as moderated or unmoderated (they are both in the active file and the checkgroups but their status differs) and the relevant ctlinnd commands to fix that;
  • Descriptions which should be removed (they are in the newsgroups file but not in the checkgroups);
  • Descriptions which should be added (they are not in the newsgroups file but in the checkgroups).

The output of docheckgroups can be fed into mod-active (it will pause the news server, update the active file accordingly, reload it and resume the work of the news server) or into the shell (commands for ctlinnd will be processed one by one). In order to update the newsgroups file, the -u flag must be given to docheckgroups.

When processing a checkgroups manually, it is always advisable to first check the raw output of docheckgroups. Then, if everything looks fine, use mod-active and the -u flag.

If this flag is given, docheckgroups will update the newsgroups file: it removes obsolete descriptions and adds new ones. It also sorts this file alphabetically and improves its general format (see newsgroups(5) for an explanation of the preferred number of tabulations).

So as to better understand how docheckgroups works, here are examples with the following active file:

    a.first 0000000000 0000000001 y
    a.second.announce 0000000000 0000000001 y
    a.second.group 0000000000 0000000001 y
    b.additional 0000000000 0000000001 y
    b.third 0000000000 0000000001 y
    c.fourth 0000000000 0000000001 y

the following newsgroups file (using tabulations):

    a.first             First group.
    a.second.announce   Announce group.
    a.second.group      Second group.
    b.third             Third group.
    c.fourth            Fourth group.

and the following localgroups file (using tabulations):

    b.additional        A local newsgroup I want to keep.

The checkgroups we process is in the file test which contains:

    a.first             First group.
    a.second.announce   Announce group. (Moderated)
    a.second.group      Second group.
    b.third             Third group.
    c.fourth            Fourth group.

If we run:

    cat test | docheckgroups

docheckgroups will output that a.second.announce is incorrectly marked as unmoderated and that its description is obsolete. Besides, two new descriptions will be mentioned for addition (the new one for a.second.announce and the missing description for b.additional -- it should indeed be in the newsgroups file and not only in localgroups). Now that we have checked the output of docheckgroups and that we agree with the changes, we run it with the -u flag to update the newsgroups file and we redirect the standard output to mod-active to update the active file:

    cat test | docheckgroups -u | mod-active

That's all!

Now, suppose we run:

    cat test | docheckgroups "^c\..*$"

Nothing is output (indeed, everything is fine for the c.* hierarchy). It would have been similar if the test file had only contained the checkgroups for the c.* hierarchy (docheckgroups would not have checked a.* and b.*, even if they had been in include-pattern).

In order to check both a.* and c.*, you can run:

    cat test | docheckgroups "^a\..*$|^c\..*$"

And if you want to check a.* but not a.second.*, you can run:

    cat test | docheckgroups "^a\..*$" "^a\.second\..*$"

In our example, docheckgroups will then mention a.second.announce and a.second.group for removal since they are in the active file (the same goes for their descriptions). Notwithstanding, if you do want to keep a.second.announce, just add this group to localgroups and docheckgroups will no longer mention it for removal.

The Shell script itself used to process checkgroups.
The list of local newsgroups along with their descriptions.

Documentation written by Julien Elie for InterNetNews.

active(5), controlchan(8), ctlinnd(8), mod-active(8), newsgroups(5).

2023-09-06 INN 2.7.1