February 2004
Beginner
200 pages
5h 40m
English
groups | Print the group membership of a user |
groupadd | Create a new group |
groupdel | Delete a group |
groupmod | Modify a group |
A group is a set of user accounts treated as a single entity. If you give permission for a group to take some action (such as modify a file), then all members of that group can take it. For example, you can give full permissions for the group friends to read, write, and execute the file /tmp/sample:
$ groups users smith friends $ chgrp friends /tmp/sample $ chmod 770 /tmp/sample $ ls -l /tmp/sample -rwxrwx--- 1 smith friends 2874 Oct 20 22:35 /tmp/sample
To add users to a group, edit /etc/group as root.[16] To change the group ownership of a file, recall the chgrp commands from File Properties.
[16] Different systems may store the group member list in other ways.