UNIX for Advanced & Expert Users

Code:

tr ':' ' ' </etc/group | while read g x
do
 if [ "$g" = "$MY_TRIAL_GROUP" ]
 then
   echo "Used: $g $x" >&2
   break
 fi
done

awk might be used too, but this would also miss group entries stored elsewhere than /etc/group.

Code:

awk -F: '$1 == "'$MY_TRIAL_GROUP'" {printf("Used: %s\n",$0)}' /etc/group

getent group was designed to avoid this issue, no need to handcraft incomplete solutions.

Command id takes an ID not a Group (although some name them alike, they are two different name spaces). You can get all the IDs of a group with -G as described here: Man Page for id (linux Section 1) - The UNIX and Linux Forums

If you know nis or yp is in use, the data equivalent to /etc/passwd is 'niscat passwd' or 'ypcat passwd'. It includes the local /etc/passwd entries:

Code:

$ ypcat passwd|grep -i <my_id>
my_id:MY_ID@this_corp.com:6068:6900:David Pickett|MY_ID:/home_dir_path:/usr/bin/ksh
$

For group, there is 'niscat group' and 'ypcat group'. You can grep for groups and users.

Indeed, that's the reason why I'm suggesting to use getent which can search both the passwd and group database (beyond others).
More precisely, you get all the group IDs of a user with this command, which is not what the OP is asking for.
Are you sure of that ? IMHO, that would be a bug of Linux ypcat if it really does.
That's a strange password field, I would expect "*" there.
But here again, they would likely miss /etc/group entries (at least if they work as specified/documented) and they would definitely miss ldap entries.
which is precisely what the OP wants to avoid.

So, in a positive vein, what is the ldap equivalent of "ypcat passwd" and "ypcat group"? We could pile up all the possibilities inside parens in bash, feeding "| sort -u ".

That would be ldaplist but Linux distributions are lacking this command .
I have found this implementation:
RPM resource ldaplist