1.\" $OpenBSD: setpgid.2,v 1.14 2013/05/08 14:19:44 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 8 2013 $ 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.Sh RETURN VALUES 59.Fn setpgid 60returns 0 when the operation was successful. 61If the request failed, \-1 is returned and the global variable 62.Va errno 63indicates the reason. 64.Sh ERRORS 65.Fn setpgid 66will fail and the process group will not be altered if: 67.Bl -tag -width Er 68.It Bq Er EACCES 69The value of the 70.Fa pid 71argument matches the process ID of a child process of the calling process, 72and the child process has successfully executed one of the exec functions. 73.It Bq Er EINVAL 74The value of the 75.Fa pgrp 76argument is less than zero. 77.It Bq Er EPERM 78The requested process is a descendant of the calling process, and 79is either a session leader or not in the same session as the calling 80process. 81.It Bq Er EPERM 82The value of the 83.Fa pgid 84argument is neither the PID of the process indicated by the 85.Fa pid 86argument nor the process group ID of an existing process group in 87the same session as the calling process. 88.It Bq Er ESRCH 89The value of the 90.Fa pid 91argument does not match the process ID of the calling process or of a 92descendant of the calling process. 93.El 94.Sh SEE ALSO 95.Xr getpgrp 2 , 96.Xr setsid 2 97.Sh STANDARDS 98.Fn setpgrp 99is identical to 100.Fn setpgid , 101and is retained for calling convention compatibility with historical 102versions of 103.Bx . 104.Pp 105The 106.Fn setpgid 107function conforms to 108.St -p1003.1-2008 . 109