[CentOS] Shell script to list group members

[Barry Brimer]

Quoting Tim Alberts <talberts at msiscales.com>:

> I have several shell scripts to manage user accounts on a server.  I've
> been using a file with the usernames of peoples accounts that any script
> needs to process.  I had a thought that I can and should be setting up
> groups and adding user accounts to those groups so I don't have to
> maintain a set of files with the user accounts.
>
> So essentially, I am looking for a (simple) shell command to run from a
> bash script that will allow me to list user accounts that belong to a
> particular group.  Any help is appreciated.

With spaces separating groups:

egrep -e '^groupname:' /etc/group | awk -F : '{ print $4 }' | sed -e 's/,/ /g'

With commas separating groups:

egrep -e '^groupname:' /etc/group | awk -F : '{ print $4 }'