irix - group (4)

     group - group membership file

     The /etc/group file contains for each group the following information:

	o group	name

	o encrypted password

	o numerical group ID

	o a comma separated list of all	users allowed in the group

     For example, the entry for	the sys	group is:

	  sys::0:root,bin,sys,adm


     This is an	ASCII file. A ``#'' at the beginning of	a line indicates a
     comment.  The ``#'' is only recognized at the beginning of	a line,	it
     should not	be used	after the user list.  The fields are separated by
     colons; each group	is separated from the next by a	new-line.  Except at
     the beginning of each line, white-space is	not ignored, thus in most
     cases there should	be no spaces e.g. in the user list.  If	the password
     field is null, no password	is demanded.  A	``*'' in the password field
     locks the entry.

     This file resides in the /etc directory.  Because of the encrypted
     passwords,	it can and does	have general read permission and can be	used,
     for example, to map numerical group ID's to names.

     If	the NFS	option is installed, a group file can have a line beginning
     with a plus (+), which means to incorporate entries from the NIS group
     database.	There are two styles of	+ entries:  All	by itself, + means to
     insert the	entire contents	of the NIS group database at that point; +name
     means to insert the entry (if any)	for name from the NIS database at that
     point.  If	a + entry has a	non-null password or group member field, the
     contents of that field will override what is contained in the NIS
     database.	The numerical group ID field cannot be overridden.

     A group file can also have	a line beginning with a	minus (-), these
     entries are used to disallow group	entries.  There	is only	one style of -
     entries:  an entry	that consists of -name means to	disallow any
     subsequent	entry (if any) for name.  These	entries	will be	disallowed
     regardless	of whether the subsequent entry	comes from the NIS or the
     local group file.

     For example, if the following entries



	  -oldproj
	  +myproject:::bill, steve
	  +:

     appear at the end of a group file,	then the group oldproj will be ignored
     if	it appears after the entry -oldproj.  Also, the	group myproject	will
     have members bill and steve, and the password and group ID	of the NIS
     entry for the group myproject.  All the groups listed in the NIS database
     will be pulled in and placed after	the entry for myproject.

     /etc/group

     crypt(3), newgrp(1M), passwd(1), passwd(4)

     The passwd(1) command won't change	group passwords.