Groups

Group Passwords

In older versions of UNIX, you could belong to only a single group. The newgrp command enabled you to change to another group. You can see that the /etc/group file still has a field for a group password. This is rarely used today because a user can belong to many groups simultaneously.

Another system file worth mentioning is the group file. This file also resides in the /etc directory and maintains a list of the primary and associated groups to which you belong. Take a look at an example of a group file and identify the components that comprise it:

root::0:root other::1:root,hpdb bin::2:root,bin sys::3:root,uucp adm::4:root,adm daemon::5:root,daemon mail::6:root lp::7:root,lp tty::10: developer::99:dwilson,ssmith,cfliss ...

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