1.\" Copyright (c) 2000 2.\" Sheldon Hearn. 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.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES 19.\" 20.\" $FreeBSD: src/lib/libc/sys/setresuid.2,v 1.2.2.8 2001/12/14 18:34:01 ru Exp $ 21.\" $DragonFly: src/lib/libc/sys/setresuid.2,v 1.4 2007/08/03 08:40:14 swildner Exp $ 22.\" 23.Dd August 3, 2007 24.Dt SETRESUID 2 25.Os 26.Sh NAME 27.Nm getresgid , 28.Nm getresuid , 29.Nm setresgid , 30.Nm setresuid 31.Nd get or set real, effective and saved user or group ID 32.Sh LIBRARY 33.Lb libc 34.Sh SYNOPSIS 35.In sys/types.h 36.In unistd.h 37.Ft int 38.Fn getresgid "gid_t *rgid" "gid_t *egid" "gid_t *sgid" 39.Ft int 40.Fn getresuid "uid_t *ruid" "uid_t *euid" "uid_t *suid" 41.Ft int 42.Fn setresgid "gid_t rgid" "gid_t egid" "gid_t sgid" 43.Ft int 44.Fn setresuid "uid_t ruid" "uid_t euid" "uid_t suid" 45.Sh DESCRIPTION 46The 47.Fn setresuid 48system call sets the real, 49effective and saved user IDs of the current process. 50The analogous 51.Fn setresgid 52sets the real, effective and saved group IDs. 53.Pp 54Privileged processes may set these IDs 55to arbitrary values. 56Unprivileged processes are restricted 57in that each of the new IDs must match one of the current IDs. 58.Pp 59Passing -1 as an argument causes the corresponding value 60to remain unchanged. 61.Pp 62The 63.Fn getresgid 64and 65.Fn getresuid 66calls retrieve the real, effective, and saved group and user IDs of 67the current process, respectively. 68.Sh RETURN VALUES 69.Rv -std 70.Sh ERRORS 71.Bl -tag -width Er 72.It Bq Er EFAULT 73An address passed to 74.Fn getresgid 75or 76.Fn getresuid 77was invalid. 78.It Bq Er EPERM 79The calling process was not privileged 80and tried to change one or more IDs to a value 81which was not the current real ID, the current effective ID 82nor the current saved ID. 83.El 84.Sh SEE ALSO 85.Xr getegid 2 , 86.Xr geteuid 2 , 87.Xr getgid 2 , 88.Xr getuid 2 , 89.Xr issetugid 2 , 90.Xr setgid 2 , 91.Xr setregid 2 , 92.Xr setreuid 2 , 93.Xr setuid 2 94.Sh STANDARDS 95These system calls are not available on many platforms. 96They exist in 97.Dx 98to support Linux binaries linked against GNU libc2. 99.Sh HISTORY 100These system calls first appeared in HP-UX. 101