4.3BSD-UWisc/man/man5/group.5

.\" @(#)group.5 1.1 85/12/28 SMI; from UCB 4.2
.TH GROUP 5 "1 February 1985"
.SH NAME
group \- group file
.SH SYNOPSIS
.B /etc/group
.SH DESCRIPTION
.IX  "group file"  ""  "\fLgroup\fP \(em group file format"
.I Group
contains for each group the following information:
.IP \(bu 2
group name
.IP \(bu 2
encrypted password
.IP \(bu 2
numerical group ID
.IP \(bu 2
a comma separated list of all users allowed in the group
.LP
This is an
.SM ASCII
file.  The fields are separated by colons;
each group is separated from the next by a new-line.
If the password field is null, no password is demanded.
.LP
This file resides in the
.I /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.
.PP
A group file can have a line beginning with a plus (+),
which means to incorporate entries from the yellow pages.
There are two styles of + entries:
All by itself, + means to insert the entire contents
of the yellow pages group file at that point;
.I +name
means to insert the entry (if any) for
.I name
from the yellow pages at that point.
If a + entry has a non-null password or group member field,
the contents of that field will overide
what is contained in the yellow pages.
The numerical group ID field cannot be overridden.
.SH EXAMPLE
.PP
.ft L
.nf
+myproject:::bill, steve
+:
.fi
.PP
If these entries appear at the end of a group file, then the group
.I myproject
will have members
.IR bill and steve ,
and the password and group ID of the yellow pages entry for the group
.IR myproject .
All the groups listed in the yellow pages
will be pulled in and placed after the entry for
.IR myproject .
.SH FILES
/etc/group
/etc/yp/group
.SH "SEE ALSO"
setgroups(2), initgroups(3), crypt(3), passwd(1), passwd(5)
.SH BUGS
The
.IR passwd (1)
command won't change group passwords.