GROUP(5) Linux Programmer's Manual GROUP(5)
group - user group file
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)
This page is part of release 4.10 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/. Linux 2016-10-08 GROUP(5)
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