The /etc/group file is a text file that defines the groups on the system.
There is one entry per line, with the following format:
group_name:password:GID:user_list
The fields are as follows:
- group_name
- the name of the group.
- password
- the (encrypted) group password. If this field is empty, no password is
needed.
- GID
- the numeric group ID.
- user_list
- a list of the usernames that are members of this group, separated by
commas.
As the 4.2BSD initgroups(3) man page says: no one seems to keep
/etc/group up-to-date.
chgrp(1), gpasswd(1), groups(1), login(1),
newgrp(1), sg(1), getgrent(3), getgrnam(3),
gshadow(5), passwd(5), vigr(8)
This page is part of release 5.05 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the latest
version of this page, can be found at https://www.kernel.org/doc/man-pages/.