StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

POPerl or Python script to remove user from group
text
Body
copied!<p>I am putting together a Samba-based server as a Primary Domain Controller, and ran into a cute little problem that should have been solved many times over. But a number of searches did not yield a result. I need to be able to remove an existing user from an existing group with a command line script. It appears that the usermod easily allows me to add a user to a supplementary group with this command:</p> <pre><code>usermod -a -G supgroup1,supgroup2 username </code></pre> <p>Without the "-a" option, if the user is currently a member of a group which is not listed, the user will be removed from the group. Does anyone have a perl (or Python) script that allows the specification of a user and group for removal? Am I missing an obvious existing command, or well-known solution forthis? Thanks in advance!</p> <p>Thanks to J.J. for the pointer to the Unix::Group module, which is part of Unix-ConfigFile. It looks like the command deluser would do what I want, but was not in any of my existing repositories. I went ahead and wrote the perl script using the Unix:Group Module. Here is the script for your sysadmining pleasure.</p> <pre><code>#!/usr/bin/perl # # Usage: removegroup.pl login group # Purpose: Removes a user from a group while retaining current primary and # supplementary groups. # Notes: There is a Debian specific utility that can do this called deluser, # but I did not want any cross-distribution dependencies # # Date: 25 September 2008 # Validate Arguments (correct number, format etc.) if ( ($#ARGV < 1) || (2 < $#ARGV) ) { print "\nUsage: removegroup.pl login group\n\n"; print "EXIT VALUES\n"; print " The removeuser.pl script exits with the following values:\n\n"; print " 0 success\n\n"; print " 1 Invalid number of arguments\n\n"; print " 2 Login or Group name supplied greater than 16 characters\n\n"; print " 3 Login and/or Group name contains invalid characters\n\n"; exit 1; } # Check for well formed group and login names if ((16 < length($ARGV[0])) ||(16 < length($ARGV[1]))) { print "Usage: removegroup.pl login group\n"; print "ERROR: Login and Group names must be less than 16 Characters\n"; exit 2; } if ( ( $ARGV[0] !~ m{^[a-z_]+[a-z0-9_-]*$}) || ( $ARGV[0] !~ m{^[a-z_]+[a-z0-9_-]*$} ) ) { print "Usage: removegroup.pl login group\n"; print "ERROR: Login and/or Group name contains invalid characters\n"; exit 3; } # Set some variables for readability $login=$ARGV[0]; $group=$ARGV[1]; # Requires the GroupFile interface from perl-Unix-Configfile use Unix::GroupFile; $grp = new Unix::GroupFile "/etc/group"; $grp->remove_user("$group", "$login"); $grp->commit(); undef $grp; exit 0; </code></pre>

Querying!

Guidance

An individual column

Larger individual text columns get their own page to allow for proper reading.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload