1.\" Copyright (c) 1980, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.Dd February 8, 2004 29.Dt SETPGID 2 30.Os 31.Sh NAME 32.Nm setpgid , 33.Nm setpgrp 34.Nd set process group 35.Sh LIBRARY 36.Lb libc 37.Sh SYNOPSIS 38.In unistd.h 39.Ft int 40.Fn setpgid "pid_t pid" "pid_t pgrp" 41.Ft int 42.Fn setpgrp "pid_t pid" "pid_t pgrp" 43.Sh DESCRIPTION 44The 45.Fn setpgid 46system call 47sets the process group of the specified process 48.Fa pid 49to the specified 50.Fa pgrp . 51If 52.Fa pid 53is zero, then the call applies to the current process. 54If 55.Fa pgrp 56is zero, then the process id of the process specified by 57.Fa pid 58is used instead. 59.Pp 60If the affected process is not the invoking process, then it must be a 61child of the invoking process, it must not have performed an 62.Xr exec 3 63operation, and both processes must be in the same session. 64The requested process group ID must already exist in the session of 65the caller, or it must be equal to the target process ID. 66.Sh RETURN VALUES 67.Rv -std setpgid 68.Sh COMPATIBILITY 69The 70.Fn setpgrp 71system call 72is identical to 73.Fn setpgid , 74and is retained for calling convention compatibility with historical 75versions of 76.Bx . 77.Sh ERRORS 78The 79.Fn setpgid 80system call 81will fail and the process group will not be altered if: 82.Bl -tag -width Er 83.It Bq Er EINVAL 84The requested process group ID is not legal. 85.It Bq Er ESRCH 86The requested process does not exist. 87.It Bq Er ESRCH 88The target process is not the calling process or 89a child of the calling process. 90.It Bq Er EACCES 91The requested process is a child of the calling process, 92but it has performed an 93.Xr exec 3 94operation. 95.It Bq Er EPERM 96The target process is a session leader. 97.It Bq Er EPERM 98The requested process group ID is not in the session of the caller, 99and it is not equal to the process ID of the target process. 100.El 101.Sh SEE ALSO 102.Xr getpgrp 2 103.Sh STANDARDS 104The 105.Fn setpgid 106system call is expected to conform to 107.St -p1003.1-90 . 108