[apple/xnu.git] / bsd / man / man2 / setregid.2

.\" Copyright (c) 1980, 1991, 1993, 1994
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
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.\" 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.
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.\"     @(#)setregid.2	8.2 (Berkeley) 4/16/94
.\" $FreeBSD: src/lib/libc/sys/setregid.2,v 1.6.2.4 2001/12/14 18:34:01 ru Exp $
.\"
.Dd April 16, 1994
.Dt SETREGID 2
.Os
.Sh NAME
.Nm setregid
.Nd set real and effective group ID
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In unistd.h
.Ft int
.Fn setregid "gid_t rgid" "gid_t egid"
.Sh DESCRIPTION
The real and effective group ID's of the current process
are set to the arguments.
Unprivileged users may change the real group
ID to the effective group ID and vice-versa; only the super-user may
make other changes.
.Pp
Supplying a value of -1 for either the real or effective
group ID forces the system to substitute the current
ID in place of the -1 parameter.
.Pp
The
.Fn setregid
function was intended to allow swapping
the real and effective group IDs
in set-group-ID programs to temporarily relinquish the set-group-ID value.
This function did not work correctly;
its purpose is now better served by the use of the
.Fn setegid
function (see
.Xr setuid 2 ) .
.Pp
When setting the real and effective group IDs to the same value,
the standard
.Fn setgid
function is preferred.
.Sh RETURN VALUES
.Rv -std setregid
.Sh ERRORS
.Bl -tag -width Er
.It Bq Er EPERM
The current process is not the super-user and a change
other than changing the effective group-id to the real group-id
was specified.
.El
.Sh SEE ALSO
.Xr getgid 2 ,
.Xr issetugid 2 ,
.Xr setegid 2 ,
.Xr setgid 2 ,
.Xr setuid 2
.Sh HISTORY
The
.Fn setregid
system call appeared in
.Bx 4.2 .
Commit	Line	Data
6d2010ae A	1	.\" Copyright (c) 1980, 1991, 1993, 1994
	2	.\" The Regents of the University of California. All rights reserved.
	3	.\"
	4	.\" Redistribution and use in source and binary forms, with or without
	5	.\" modification, are permitted provided that the following conditions
	6	.\" are met:
	7	.\" 1. Redistributions of source code must retain the above copyright
	8	.\" notice, this list of conditions and the following disclaimer.
	9	.\" 2. Redistributions in binary form must reproduce the above copyright
	10	.\" notice, this list of conditions and the following disclaimer in the
	11	.\" documentation and/or other materials provided with the distribution.
	12	.\" 3. All advertising materials mentioning features or use of this software
	13	.\" must display the following acknowledgement:
	14	.\" This product includes software developed by the University of
	15	.\" California, Berkeley and its contributors.
	16	.\" 4. Neither the name of the University nor the names of its contributors
	17	.\" may be used to endorse or promote products derived from this software
	18	.\" without specific prior written permission.
	19	.\"
	20	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	21	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	24	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	.\" SUCH DAMAGE.
	31	.\"
	32	.\" @(#)setregid.2 8.2 (Berkeley) 4/16/94
	33	.\" $FreeBSD: src/lib/libc/sys/setregid.2,v 1.6.2.4 2001/12/14 18:34:01 ru Exp $
	34	.\"
	35	.Dd April 16, 1994
	36	.Dt SETREGID 2
	37	.Os
	38	.Sh NAME
	39	.Nm setregid
	40	.Nd set real and effective group ID
	41	.Sh LIBRARY
	42	.Lb libc
	43	.Sh SYNOPSIS
	44	.In unistd.h
	45	.Ft int
	46	.Fn setregid "gid_t rgid" "gid_t egid"
	47	.Sh DESCRIPTION
	48	The real and effective group ID's of the current process
	49	are set to the arguments.
	50	Unprivileged users may change the real group
	51	ID to the effective group ID and vice-versa; only the super-user may
	52	make other changes.
	53	.Pp
	54	Supplying a value of -1 for either the real or effective
	55	group ID forces the system to substitute the current
	56	ID in place of the -1 parameter.
	57	.Pp
	58	The
	59	.Fn setregid
	60	function was intended to allow swapping
	61	the real and effective group IDs
	62	in set-group-ID programs to temporarily relinquish the set-group-ID value.
	63	This function did not work correctly;
	64	its purpose is now better served by the use of the
65	.Fn setegid
66	function (see
67	.Xr setuid 2 ) .
68	.Pp
69	When setting the real and effective group IDs to the same value,
70	the standard
71	.Fn setgid
72	function is preferred.
73	.Sh RETURN VALUES
74	.Rv -std setregid
75	.Sh ERRORS
76	.Bl -tag -width Er
77	.It Bq Er EPERM
78	The current process is not the super-user and a change
79	other than changing the effective group-id to the real group-id
80	was specified.
81	.El
82	.Sh SEE ALSO
83	.Xr getgid 2 ,
84	.Xr issetugid 2 ,
85	.Xr setegid 2 ,
86	.Xr setgid 2 ,
87	.Xr setuid 2
88	.Sh HISTORY
89	The
90	.Fn setregid
91	system call appeared in
92	.Bx 4.2 .