1.\" $OpenBSD: getuid.2,v 1.7 2000/10/18 05:12:10 aaron Exp $ 2.\" $NetBSD: getuid.2,v 1.6 1995/02/27 12:33:37 cgd Exp $ 3.\" 4.\" Copyright (c) 1980, 1991, 1993 5.\" The Regents of the University of California. All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. All advertising materials mentioning features or use of this software 16.\" must display the following acknowledgement: 17.\" This product includes software developed by the University of 18.\" California, Berkeley and its contributors. 19.\" 4. Neither the name of the University nor the names of its contributors 20.\" may be used to endorse or promote products derived from this software 21.\" without specific prior written permission. 22.\" 23.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33.\" SUCH DAMAGE. 34.\" 35.\" @(#)getuid.2 8.1 (Berkeley) 6/4/93 36.\" 37.Dd June 4, 1993 38.Dt GETUID 2 39.Os 40.Sh NAME 41.Nm getuid , 42.Nm geteuid 43.Nd get user identification 44.Sh SYNOPSIS 45.Fd #include <sys/types.h> 46.Fd #include <unistd.h> 47.Ft uid_t 48.Fn getuid void 49.Ft uid_t 50.Fn geteuid void 51.Sh DESCRIPTION 52The 53.Fn getuid 54function returns the real user ID of the calling process. 55The 56.Fn geteuid 57function returns the effective user ID of the calling process. 58.Pp 59The real user ID is that of the user who has invoked the program. 60As the effective user ID 61gives the process additional permissions during 62execution of 63.Dq Em set-user-ID 64mode processes, 65.Fn getuid 66is used to determine the real user ID of the calling process. 67.Sh ERRORS 68The 69.Fn getuid 70and 71.Fn geteuid 72functions are always successful, and no return value is reserved to 73indicate an error. 74.Sh SEE ALSO 75.Xr getgid 2 , 76.Xr setreuid 2 , 77.Xr setuid 2 78.Sh STANDARDS 79The 80.Fn getuid 81and 82.Fn geteuid 83functions conform to 84.St -p1003.1-88 . 85