1.\" $OpenBSD: getgid.2,v 1.8 1999/06/29 14:09:58 aaron Exp $ 2.\" $NetBSD: getgid.2,v 1.5 1995/02/27 12:32:53 cgd Exp $ 3.\" 4.\" Copyright (c) 1983, 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.\" @(#)getgid.2 8.1 (Berkeley) 6/4/93 36.\" 37.Dd June 4, 1993 38.Dt GETGID 2 39.Os 40.Sh NAME 41.Nm getgid , 42.Nm getegid 43.Nd get group process identification 44.Sh SYNOPSIS 45.Fd #include <sys/types.h> 46.Fd #include <unistd.h> 47.Ft gid_t 48.Fn getgid void 49.Ft gid_t 50.Fn getegid void 51.Sh DESCRIPTION 52The 53.Fn getgid 54function returns the real group ID of the calling process, 55.Fn getegid 56returns the effective group ID of the calling process. 57.Pp 58The real group ID is specified at login time. 59.Pp 60The real group ID is the group of the user who invoked the program. 61As the effective group ID gives the process additional permissions 62during the execution of 63.Dq Em set-group-ID 64mode processes, 65.Fn getgid 66is used to determine the real group ID of the calling process. 67.Sh ERRORS 68The 69.Fn getgid 70and 71.Fn getegid 72functions are always successful, and no return value is reserved to 73indicate an error. 74.Sh SEE ALSO 75.Xr getuid 2 , 76.Xr setgid 2 , 77.Xr setregid 2 78.Sh STANDARDS 79The 80.Fn getgid 81and 82.Fn getegid 83functions conform to 84.St -p1003.1-88 . 85