1.\" Copyright (c) 1980, 1991 Regents of the University of California. 2.\" 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.\" $OpenBSD: killpg.3,v 1.14 2017/05/07 21:19:29 millert Exp $ 29.\" 30.Dd $Mdocdate: May 7 2017 $ 31.Dt KILLPG 3 32.Os 33.Sh NAME 34.Nm killpg 35.Nd send signal to a process group 36.Sh SYNOPSIS 37.In signal.h 38.Ft int 39.Fn killpg "pid_t pgrp" "int sig" 40.Sh DESCRIPTION 41The 42.Fn killpg 43function sends the signal 44.Fa sig 45to the process group 46.Fa pgrp . 47See 48.Xr sigaction 2 49for a list of signals. 50If 51.Fa pgrp 52is 0, 53.Fn killpg 54sends the signal to the sending process's process group. 55.Pp 56The sending process and members of the process group must 57have the same effective user ID, or 58the sender must be the superuser. 59As a single special case the continue signal SIGCONT may be sent 60to any process with the same session ID as the caller. 61.Sh RETURN VALUES 62.Rv -std 63.Sh ERRORS 64.Fn killpg 65will fail and no signal will be sent if: 66.Bl -tag -width Er 67.It Bq Er EINVAL 68.Fa sig 69is not a valid signal number. 70.It Bq Er ESRCH 71No process can be found in the process group specified by 72.Fa pgrp . 73.It Bq Er ESRCH 74The process group was given as 0 75but the sending process does not have a process group. 76.It Bq Er EPERM 77The sending process is not the superuser and one or more 78of the target processes has an effective user ID different from that 79of the sending process. 80.El 81.Sh SEE ALSO 82.Xr getpgrp 2 , 83.Xr kill 2 , 84.Xr sigaction 2 85.Sh STANDARDS 86The 87.Fn killpg 88function conforms to the X/Open System Interfaces option of the 89.St -p1003.1-2008 90specification. 91.Pp 92The handling of process group 0 is an extension to that standard. 93.Sh HISTORY 94The 95.Fn killpg 96function call appeared in 97.Bx 4.0 . 98