1.\" $OpenBSD: setpgid.2,v 1.12 2007/05/31 19:19:33 jmc Exp $ 2.\" $NetBSD: setpgid.2,v 1.8 1995/02/27 12:36:55 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. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)setpgid.2 8.1 (Berkeley) 6/4/93 32.\" 33.Dd $Mdocdate: May 31 2007 $ 34.Dt SETPGID 2 35.Os 36.Sh NAME 37.Nm setpgid , 38.Nm setpgrp 39.Nd set process group 40.Sh SYNOPSIS 41.Fd #include <unistd.h> 42.Ft int 43.Fn setpgid "pid_t pid" "pid_t pgrp" 44.Ft int 45.Fn setpgrp "pid_t pid" "pid_t pgrp" 46.Sh DESCRIPTION 47.Fn setpgid 48sets the process group of the specified process 49.Ar pid 50to the specified 51.Ar pgrp . 52If 53.Ar pid 54is zero, then the call applies to the current process. 55If 56.Ar pgrp 57is zero, the process ID of the specified process is used. 58.Pp 59If the invoker is not the superuser, then the affected process 60must have the same effective user ID as the invoker or be a descendant 61of the invoking process. 62.Sh RETURN VALUES 63.Fn setpgid 64returns 0 when the operation was successful. 65If the request failed, \-1 is returned and the global variable 66.Va errno 67indicates the reason. 68.Sh ERRORS 69.Fn setpgid 70will fail and the process group will not be altered if: 71.Bl -tag -width Er 72.It Bq Er EACCES 73The value of the 74.Fa pid 75argument matches the process ID of a child process of the calling process, 76and the child process has successfully executed one of the exec functions. 77.It Bq Er EINVAL 78The value of the 79.Fa pgrp 80argument is less than zero. 81.It Bq Er EPERM 82The effective user ID of the requested process is different 83from that of the caller and the process is not a descendant 84of the calling process. 85.It Bq Er ESRCH 86The value of the 87.Fa pid 88argument does not match the process ID of the calling process or of a 89child process of the calling process. 90.El 91.Sh SEE ALSO 92.Xr getpgrp 2 93.Sh STANDARDS 94.Fn setpgrp 95is identical to 96.Fn setpgid , 97and is retained for calling convention compatibility with historical 98versions of 99.Bx . 100.Pp 101The 102.Fn setpgid 103function conforms to 104.St -p1003.1-88 . 105