freebsd-skq/lib/libc/sys/setreuid.2

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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\"     @(#)setreuid.2	8.2 (Berkeley) 4/16/94
.\" $FreeBSD$
.\"
.Dd February 8, 2001
.Dt SETREUID 2
.Os
.Sh NAME
.Nm setreuid
.Nd set real and effective user ID's
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In unistd.h
.Ft int
.Fn setreuid "uid_t ruid" "uid_t euid"
.Sh DESCRIPTION
The real and effective user IDs of the
current process are set according to the arguments.
If
.Fa ruid
or
.Fa euid
is -1, the current uid is filled in by the system.
Unprivileged users may change the real user
ID to the effective user ID and vice-versa; only the super-user may
make other changes.
.Pp
If the real user ID is changed (i.e.\&
.Fa ruid
is not -1) or the effective user ID is changed to something other than
the real user ID, then the saved user ID will be set to the effective user ID.
.Pp
The
.Fn setreuid
system call has been used to swap the real and effective user IDs
in set-user-ID programs to temporarily relinquish the set-user-ID value.
This purpose is now better served by the use of the
.Xr seteuid 2
system call.
.Pp
When setting the real and effective user IDs to the same value,
the standard
.Fn setuid
system call is preferred.
.Sh RETURN VALUES
.Rv -std setreuid
.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 user-id to the real user-id
was specified.
.El
.Sh SEE ALSO
.Xr getuid 2 ,
.Xr issetugid 2 ,
.Xr seteuid 2 ,
.Xr setuid 2
.Sh HISTORY
The
.Fn setreuid
system call appeared in
.Bx 4.2 .
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.\" 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.`
Renumber copyright clause 4 Renumber cluase 4 to 3, per what everybody else did when BSD granted them permission to remove clause 3. My insistance on keeping the same numbering for legal reasons is too pedantic, so give up on that point. Submitted by: Jan Schaumann <jschauma@stevens.edu> Pull Request: https://github.com/freebsd/freebsd/pull/96 2017-02-28 23:42:47 +00:00			`.\" 3. Neither the name of the University nor the names of its contributors`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.\" 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.`
			`.\"`
			`.\" @(#)setreuid.2 8.2 (Berkeley) 4/16/94`
$Id$ -> $FreeBSD$ 1999-08-28 00:22:10 +00:00			`.\" $FreeBSD$`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.\"`
mdoc(7) police: prevent generation of the extra whitespace after ``i.e.'', use .Rv, update .Dd. 2001-02-09 12:47:23 +00:00			`.Dd February 8, 2001`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Dt SETREUID 2`
mdoc(7) police: removed HISTORY info from the .Os call. 2001-07-10 13:41:46 +00:00			`.Os`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Sh NAME`
			`.Nm setreuid`
			`.Nd set real and effective user ID's`
Introduce ".Lb" macro to libc manpages. More libraries manpages updates following. 2000-04-21 09:42:15 +00:00			`.Sh LIBRARY`
			`.Lb libc`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Sh SYNOPSIS`
mdoc(7) police: Use the new .In macro for #include statements. 2001-10-01 16:09:29 +00:00			`.In unistd.h`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Ft int`
			`.Fn setreuid "uid_t ruid" "uid_t euid"`
			`.Sh DESCRIPTION`
			`The real and effective user IDs of the`
			`current process are set according to the arguments.`
			`If`
			`.Fa ruid`
Remove whitespace at EOL. 2001-07-15 07:53:42 +00:00			`or`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Fa euid`
			`is -1, the current uid is filled in by the system.`
			`Unprivileged users may change the real user`
			`ID to the effective user ID and vice-versa; only the super-user may`
			`make other changes.`
			`.Pp`
mdoc(7) police: prevent generation of the extra whitespace after ``i.e.'', use .Rv, update .Dd. 2001-02-09 12:47:23 +00:00			`If the real user ID is changed (i.e.\&`
Document the cases in which setreuid changes the saved-user-ID. 2001-02-08 12:43:33 +00:00			`.Fa ruid`
			`is not -1) or the effective user ID is changed to something other than`
			`the real user ID, then the saved user ID will be set to the effective user ID.`
			`.Pp`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`The`
			`.Fn setreuid`
mdoc(7) police: Tidy up the syscall language. Stop calling system calls "function calls". Use "The .Fn system call" a-la "The .Nm utility". When referring to a non-BSD implementation in the HISTORY section, call syscall a function, to be safe. 2002-12-18 09:22:32 +00:00			`system call has been used to swap the real and effective user IDs`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`in set-user-ID programs to temporarily relinquish the set-user-ID value.`
			`This purpose is now better served by the use of the`
mdoc(7) police: Tidy up the syscall language. Stop calling system calls "function calls". Use "The .Fn system call" a-la "The .Nm utility". When referring to a non-BSD implementation in the HISTORY section, call syscall a function, to be safe. 2002-12-18 09:22:32 +00:00			`.Xr seteuid 2`
			`system call.`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Pp`
			`When setting the real and effective user IDs to the same value,`
			`the standard`
			`.Fn setuid`
mdoc(7) police: Tidy up the syscall language. Stop calling system calls "function calls". Use "The .Fn system call" a-la "The .Nm utility". When referring to a non-BSD implementation in the HISTORY section, call syscall a function, to be safe. 2002-12-18 09:22:32 +00:00			`system call is preferred.`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Sh RETURN VALUES`
Remove whitespace at EOL. 2001-07-15 07:53:42 +00:00			`.Rv -std setreuid`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Sh ERRORS`
Use `Er' variable to define first column width in ERRORS section. It was initially suggested by mdoc(7) style, but was broken over the years 2000-05-04 13:09:25 +00:00			`.Bl -tag -width Er`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.It Bq Er EPERM`
			`The current process is not the super-user and a change`
			`other than changing the effective user-id to the real user-id`
			`was specified.`
			`.El`
			`.Sh SEE ALSO`
			`.Xr getuid 2 ,`
Xref the new issetugid(2) man page where appropriate. Also add additional set*id(2) xrefs where appropriate. 1997-04-01 18:58:38 +00:00			`.Xr issetugid 2 ,`
BSD 4.4 Lite Lib Sources 1994-05-27 05:00:24 +00:00			`.Xr seteuid 2 ,`
			`.Xr setuid 2`
			`.Sh HISTORY`
			`The`
Correctly use .Fn instead of .Nm to reference function names in a bunch of man pages. Use the correct .Bx (BSD UNIX) or .At (AT&T UNIX) macros instead of explicitly specifying the version in the text in a bunch of man pages. 1996-08-22 23:31:07 +00:00			`.Fn setreuid`
Fix history info 1995-04-23 12:31:13 +00:00			`system call appeared in`
			`.Bx 4.2 .`