.\" $OpenBSD: group.5,v 1.3 1998/11/29 15:47:23 aaron Exp $ .\" $NetBSD: group.5,v 1.4 1995/07/28 06:41:39 phil Exp $ .\" .\" Copyright (c) 1980, 1991, 1993 .\" The Regents of the University of California. All rights reserved. .\" Portions Copyright(c) 1994, Jason Downs. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)group.5 8.3 (Berkeley) 4/19/94 .\" .Dd July 18, 1995 .Dt GROUP 5 .Os .Sh NAME .Nm group .Nd format of the group permissions file .Sh DESCRIPTION The file .Pa /etc/group consists of newline separated .Tn ASCII records, one per group, containing four colon .Pq Sq \&: separated fields. These fields are as follows: .Pp .Bl -tag -width password -offset indent -compact .It group Name of the group. .It passwd Group's encrypted password. .It gid The group's decimal ID. .It member Group members. .El .Pp The .Ar group field is the group name used for granting file access to users who are members of the group. The .Ar gid field is the number associated with the group name. They should both be unique across the system (and often across a group of systems) since they control file access. The .Ar passwd field is an optional encrypted password. This field is rarely used and an asterisk is normally placed in it rather than leaving it blank. The .Ar member field contains the names of users granted the privileges of .Ar group . The member names are separated by commas without spaces or newlines. A user is automatically in a group if that group was specified in their .Pa /etc/passwd entry and does not need to be added to that group in the .Pa /etc/group file. .\" .Pp .\" When the system reads the file .\" .Pa /etc/group .\" the fields are read into the structure .\" .Fa group .\" declared in .\" .Aq Pa grp.h : .\" .Bd -literal -offset indent .\" struct group { .\" char *gr_name; /* group name */ .\" char *gr_passwd; /* group password */ .\" int gr_gid; /* group id */ .\" char **gr_mem; /* group members */ .\" }; .\" .Ed .Sh YP SUPPORT If YP is active, the .Nm file may also contain lines of the format .Pp .Bl -tag -offset indent -compact +name:*:: .Pp which causes the specified group to be included from the .Pa group.byname YP map. .Pp If no group name is specified, or the .Dq + (plus sign) appears alone on line, all groups are included from the YP map. .Pp YP references may appear anywhere in the file, but the single .Dq + form should be on the last line, for historical reasons. Only the first group with a specific name encountered, whether in the .Nm file itself, or included via YP, will be used. .Sh FILES .Bl -tag -width /etc/group -compact .It Pa /etc/group .El .Sh SEE ALSO .Xr passwd 1 , .Xr setgroups 2 , .Xr crypt 3 , .Xr initgroups 3 , .Xr passwd 5 , .Xr yp 8 .Sh BUGS The .Xr passwd 1 command does not change the .Nm passwords. .Sh HISTORY A .Nm file format appeared in .At v6 . .Pp YP file format first appeared in SunOS.