1.\" $NetBSD: getuid.2,v 1.6 1995/02/27 12:33:37 cgd Exp $ 2.\" 3.\" Copyright (c) 1980, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)getuid.2 8.1 (Berkeley) 6/4/93 35.\" 36.Dd June 4, 1993 37.Dt GETUID 2 38.Os BSD 4 39.Sh NAME 40.Nm geteuid , 41.Nm getuid 42.Nd get user identification 43.Sh SYNOPSIS 44.Fd #include <unistd.h> 45.Ft uid_t 46.Fo geteuid 47.Fa void 48.Fc 49.Ft uid_t 50.Fo getuid 51.Fa void 52.Fc 53.Sh DESCRIPTION 54The 55.Fn getuid 56function returns the real user ID of the calling process. 57The 58.Fn geteuid 59function 60returns the effective user ID of the calling process. 61.Pp 62The real user ID is that of the user who has invoked the program. 63As the effective user ID 64gives the process additional permissions during 65execution of 66.Dq Em set-user-ID 67mode processes, 68.Fn getuid 69is used to determine the real-user-id of the calling process. 70.Sh ERRORS 71The 72.Fn getuid 73and 74.Fn geteuid 75functions are always successful, and no return value is reserved to 76indicate an error. 77.Sh LEGACY SYNOPSIS 78.Fd #include <sys/types.h> 79.Fd #include <unistd.h> 80.Pp 81The include file 82.In sys/types.h 83is necessary for both functions. 84.Sh SEE ALSO 85.Xr getgid 2 , 86.Xr setreuid 2 , 87.Xr compat 5 88.Sh STANDARDS 89.Fn geteuid 90and 91.Fn getuid 92functions conform to 93.St -p1003.1-88 . 94