NAME

group - the group file

SYNOPSIS

/etc/group

DESCRIPTION

Each line of /etc/group is one group, four fields separated by colons:

name is the group's name, password is empty, gid its number and members the logins that have the group besides their own (their /etc/passwd group), separated by commas.

The base package ships the system's own file with the groups the add-on packages need added; a package that installs a file or device node owned by a group can be installed only when the group is in this file.

audio

(gid 20) the sound devices: their nodes, /dev/audio (which the base package ships) and /dev/paula, are readable and writable by root and by the members of audio.

ADDING A LOGIN TO A GROUP

usermod -G sets a login's whole list of extra groups, so name the ones it has as well; groups login prints them:

groups jane
usermod -G audio jane

for a login with no other extra groups, or usermod -G audio,games jane when it is in games too. A new login gets the group with useradd -G audio. The change takes effect at the login's next login.

UPDATES

The file is a configuration file of the base package: an update never overwrites a file that was changed (a group added, a member added), nor, on a system installed before the base package carried this file, the file it finds. It keeps the file and writes the new default as /etc/group.new, and the package tools list it as pending. When the new default only adds a group, add it to the kept file with groupadd, for example groupadd -g 20 audio (any free number will do: packages name the group, not its number), then remove /etc/group.new.

FILES

/etc/group

/etc/group.new

a new default waiting to be merged.

SEE ALSO

groupadd(1M), useradd(1M), usermod(1M), groups(1)