Re: adding all users to group

[Cameron Kerr <cameron@glissarok.localdomain>]

On Mon, 21 Jan 2002, dman wrote:

>On Mon, Jan 21, 2002 at 06:59:21PM -0800, mike@stonelx.ath.cx wrote:
>| Hi,
>| I'm trying to find a way to
>| add all my users to a group.
>| Is there a simple command to do this?

Simple if you can copy and paste into a file.

>Unfortunately this method will catch all system users too.  An

You can easily do this with awk, instead of sed

/bin/cat /etc/passwd | awk -F':' '
	( $3 >= 1000 ) && ( $3 < 65534 ) {
		print $1
	}'

All of the users on a Debian system have UID >= 1000. For some unknown (to
me) reason, the user `nobody' has a UID of 65534 (or -1)
That will list the local users, no biggie. Lets complete the program then,
shall we.

-------------------------- ~/bin/lsusers -----------------------
#!/bin/sh
# List all the users (non system) registered on a local system and network
# Cameron Kerr
# Born: 22 January 2002
#
# $Id: lsusers,v 0.2 2002/01/22 07:41:47 cameron Exp cameron $
# $Log: lsusers,v $
# Revision 0.2  2002/01/22 07:41:47  cameron
# Collate the output, sorting, and uniqing it.
#
# Revision 0.1  2002/01/22 07:37:22  cameron
# Initial revision
#

PATH=/bin:/usr/bin:/sbin:/usr/sbin

#Not all distributions have the same range of UIDs
system=

if [ -f /etc/slackware-version ]; then
        system=slackware
        minuid=500
        maxuid=65534 # Dummy value, really
elif [ -f /etc/debian_version ]; then
        system=debian
        minuid=1000
        maxuid=65533 # Debian `nobody' has UID of 65534
elif [ -f /etc/redhat-release ]; then
        system=redhat
        minuid=1000 # Guessing
        maxuid=65533
else
        echo "Unknown distribution. I do not know the minimum/maximim UID"
>&2
        echo "Please update this script, and send update to" >&2
        echo "cameron.kerr@paradise.net.nz" >&2
        exit 1
fi

# This should take care of any local users.
{
        cat /etc/passwd | awk -F':' '
                ( $3 >= '"$minuid"' ) && ( $3 < '"$maxuid"' ) {
                        print $1
                }'

        # We should probably take into account any NIS users.
        if [ -n "`which ypcat`" ]; then
                ypcat passwd | awk -F':' '{print $1}' 2> /dev/null
        fi

        # I don't know about LDAP...yet.
} | sort | uniq
------------------------------------------------------------

This will work (so far, on Slackware, Debian, and Redhat), with Local
accounts, and NIS accounts. More will eventually come...
Feel free to send me any updates.

Cameron Kerr
-- 
cameron.kerr@paradise.net.nz
http://homepages.paradise.net.nz/~cameronk/