group(4) [sunos man page]

group(4)							   File Formats 							  group(4)

NAME

       group - group file

DESCRIPTION

       The  group  file  is a local source of group information. The group file can be used in conjunction with other group sources, including the
       NIS maps group.byname and group.bygid, the NIS+ table group, or group information stored on an LDAP server. Programs use  the  getgrnam(3C)
       routines to access this information.

       The group file contains a one-line entry for each group recognized by the system, of the form:

	      groupname:password: gid:user-list

       where

       groupname       The name of the group.

       gid	       The group's unique numerical ID (GID) within the system.

       user-list       A comma-separated list of users allowed in the group.

       The  maximum value of the gid field is 2147483647. To maximize interoperability and compatibility, administrators are recommended to assign
       groups using the range of GIDs below 60000 where possible.

       If the password field is empty, no password is demanded. During user identification and authentication, the supplementary group access list
       is  initialized sequentially from information in this file. If a user is in more groups than the system is configured for, {NGROUPS_MAX}, a
       warning will be given and subsequent group specifications will be ignored.

       Malformed entries cause routines that read this file to halt, in which case group assignments specified further along are  never  made.	To
       prevent this from happening, use grpck(1B) to check the /etc/group database from time to time.

       Previous  releases used a group entry beginning with a `+' (plus sign) or `-' (minus sign) to selectively incorporate entries from a naming
       service source (for example, an NIS map or data from an LDAP server) for  group.  If  still  required,  this  is  supported  by	specifying
       group:compat in nsswitch.conf(4). The compat source may not be supported in future releases. Possible sources are files followed by ldap or
       nisplus. This has the effect of incorporating information from an LDAP server or the entire contents of the  NIS+  group  table	after  the
       group file.

EXAMPLES

       Example 1: Sample of a group File.

       Here is a sample group file:

       root::0:root
       stooges:q.mJzTnu8icF.:10:larry,moe,curly

       and the sample group entry from nsswitch.conf:

       group: files ldap

       With  these  entries,  the  group stooges will have members larry, moe, and curly, and all groups listed on the LDAP server are effectively
       incorporated after the entry for stooges.

       If the group file was:

       root::0:root
       stooges:q.mJzTnu8icF.:10:larry,moe,curly
       +:

       and the group entry from nsswitch.conf:

       group: compat

       all the groups listed in the NIS group.bygid and group.byname maps would be effectively incorporated after the entry for stooges.

SEE ALSO

       groups(1), grpck(1B), newgrp(1), getgrnam(3C), initgroups(3C), nsswitch.conf(4), unistd.h(3HEAD)

       System Administration Guide: Basic Administration

SunOS 5.10							    22 Jul 2004 							  group(4)

GROUP(5)						      BSD File Formats Manual							  GROUP(5)

NAME

     group -- format of the group permissions file

DESCRIPTION

     The group file /etc/group is the local source of group information.  It can be used in conjunction with the Hesiod domain 'group', and the
     NIS maps 'group.byname' and 'group.bygid', as controlled by nsswitch.conf(5).

     The group file consists of newline separated ASCII records, usually one per group, containing four colon ':' separated fields.  Each line has
     the form:
	   group:passwd:gid:[member[,member]...]

     These fields are as follows:
	   group     Name of the group.
	   passwd    Group's encrypted password.
	   gid	     The group's decimal ID.
	   member    Group members.

     The group field is the group name used for granting file access to users who are members of the group.

     The gid field is the number associated with the group name.  They should both be unique across the system (and often across a group of sys-
     tems) since they control file access.

     The 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 member field contains the names of users granted the privileges of 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 /etc/passwd entry and does not need to be added to that
     group in the /etc/group file.

     Very large groups can be accommodated over multiple lines by specifying the same group name in all of them; other than this, each line has an
     identical format to that described above.	This can be necessary to avoid the record's length limit, which is currently set to 1024 charac-
     ters.  Note that the limit can be queried through sysconf(3) by using the _SC_GETGR_R_SIZE_MAX parameter.	For example:

	   biggrp:*:1000:user001,user002,user003,...,user099,user100
	   biggrp:*:1000:user101,user102,user103,...

     The group with the name ``wheel'' has a special meaning to the su(1) command: if it exists and has any members, only users listed in that
     group are allowed to su to ``root''.

HESIOD SUPPORT

     If 'dns' is specified for the 'group' database in nsswitch.conf(5), then group lookups occur from the 'group' Hesiod domain.

NIS SUPPORT

     If 'nis' is specified for the 'group' database in nsswitch.conf(5), then group lookups occur from the 'group.byname' and 'group.bygid' NIS
     map.

COMPAT SUPPORT

     If 'compat' is specified for the 'group' database, and either 'dns' or 'nis' is specified for the 'group_compat' database in
     nsswitch.conf(5), then the group file may also contain lines of the format

     +name:*::

     which causes the specified group to be included from the 'group' Hesiod domain or the 'group.byname' NIS map (respectively).

     If no group name is specified, or the plus sign (``+'') appears alone on line, all groups are included from the Hesiod domain or the NIS map.

     Hesiod or NIS compat references may appear anywhere in the file, but the single plus sign (``+'') form should be on the last line, for his-
     torical reasons.  Only the first group with a specific name encountered, whether in the group file itself, or included via Hesiod or NIS,
     will be used.

FILES

     /etc/group

SEE ALSO

     newgrp(1), passwd(1), su(1), setgroups(2), crypt(3), initgroups(3), nsswitch.conf(5), passwd(5), yp(8)

HISTORY

     A group file format appeared in Version 6 AT&T UNIX.

     The NIS file format first appeared in SunOS.

     The Hesiod support first appeared in NetBSD 1.4.

BUGS

     The passwd(1) command does not change the group passwords.

BSD
								   June 21, 2007							       BSD