[apple/libc.git] / sys / 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:
.\" 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.
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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
5b2abdfb	1	.\" Copyright (c) 1980, 1991, 1993, 1994
e9ce8d39 A	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	.\"
5b2abdfb A	32	.\" @(#)setregid.2 8.2 (Berkeley) 4/16/94
5b2abdfb A	33	.\" $FreeBSD: src/lib/libc/sys/setregid.2,v 1.6.2.4 2001/12/14 18:34:01 ru Exp $
e9ce8d39	34	.\"
5b2abdfb A	35	.Dd April 16, 1994
5b2abdfb A	36	.Dt SETREGID 2
e9ce8d39 A	37	.Os
e9ce8d39 A	38	.Sh NAME
5b2abdfb A	39	.Nm setregid
5b2abdfb A	40	.Nd set real and effective group ID
e9ce8d39 A	41	.Sh LIBRARY
	42	.Lb libc
	43	.Sh SYNOPSIS
5b2abdfb	44	.In unistd.h
e9ce8d39	45	.Ft int
5b2abdfb	46	.Fn setregid "gid_t rgid" "gid_t egid"
e9ce8d39	47	.Sh DESCRIPTION
5b2abdfb A	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
e9ce8d39	58	The
5b2abdfb A	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.
224c7076 A	63	This function did not work correctly;
224c7076 A	64	its purpose is now better served by the use of the
5b2abdfb A	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.
e9ce8d39	73	.Sh RETURN VALUES
5b2abdfb	74	.Rv -std setregid
e9ce8d39	75	.Sh ERRORS
e9ce8d39	76	.Bl -tag -width Er
5b2abdfb A	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
e9ce8d39	82	.Sh SEE ALSO
5b2abdfb A	83	.Xr getgid 2 ,
	84	.Xr issetugid 2 ,
	85	.Xr setegid 2 ,
	86	.Xr setgid 2 ,
	87	.Xr setuid 2
e9ce8d39 A	88	.Sh HISTORY
e9ce8d39 A	89	The
5b2abdfb A	90	.Fn setregid
	91	system call appeared in
	92	.Bx 4.2 .