1.\" Copyright (c) 1996 The NetBSD Foundation, Inc. 2.\" All rights reserved. 3.\" 4.\" This code is derived from software contributed to The NetBSD Foundation 5.\" by Paul Kranenburg. 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 NetBSD 18.\" Foundation, Inc. and its contributors. 19.\" 4. Neither the name of The NetBSD Foundation nor the names of its 20.\" contributors may be used to endorse or promote products derived 21.\" from this software without specific prior written permission. 22.\" 23.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 24.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 25.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 26.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE 27.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 28.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 29.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 30.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 31.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 32.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33.\" POSSIBILITY OF SUCH DAMAGE. 34.\" 35.\" $NetBSD: psignal.9,v 1.1 1996/06/22 22:57:35 pk Exp $ 36.\" $FreeBSD: src/share/man/man9/psignal.9,v 1.7.2.2 2001/12/17 11:30:18 ru Exp $ 37.\" $DragonFly: src/share/man/man9/ksignal.9,v 1.3 2007/10/06 22:36:18 swildner Exp $ 38.\" 39.Dd June 22, 1996 40.Dt KSIGNAL 9 41.Os 42.Sh NAME 43.Nm ksignal , 44.Nm pgsignal , 45.Nm gsignal 46.Nd post signal to a process or process group 47.Sh SYNOPSIS 48.In sys/types.h 49.In sys/signalvar.h 50.Ft void 51.Fn ksignal "struct proc *p" "int signum" 52.Ft void 53.Fn pgsignal "struct pgrp *pgrp" "int signum" "int checkctty" 54.Ft void 55.Fn gsignal "int pgid" "int signum" 56.Sh DESCRIPTION 57These functions post a signal to one or more processes. 58The argument 59.Fa signum 60common to all three functions should be in the range 61.Bq 1- Ns Dv NSIG . 62.Pp 63The 64.Fn ksignal 65function posts signal number 66.Fa signum 67to the process represented by the process structure 68.Fa p . 69With a few exceptions noted below, the target process signal disposition is 70updated and is marked as runnable, so further handling of the signal is done 71in the context of the target process after a context switch. 72Note that 73.Fn ksignal 74does not by itself cause a context switch to happen. 75.Pp 76The target process is not marked as runnable in the following cases: 77.Bl -bullet -offset indent 78.It 79The target process is sleeping uninterruptibly. 80The signal will be 81noticed when the process returns from the system call or trap. 82.It 83The target process is currently ignoring the signal. 84.It 85If a stop signal is sent to a sleeping process that takes the 86default action 87(see 88.Xr sigaction 2 ) , 89the process is stopped without awakening it. 90.It 91.Dv SIGCONT 92restarts a stopped process 93(or puts them back to sleep) 94regardless of the signal action 95(e.g., blocked or ignored). 96.El 97.Pp 98If the target process is being traced 99.Fn ksignal 100behaves as if the target process were taking the default action for 101.Fa signum . 102This allows the tracing process to be notified of the signal. 103.Pp 104The 105.Fn pgsignal 106function posts signal number 107.Fa signum 108to each member of the process group described by 109.Fa pgrp . 110If 111.Fa checkctty 112is non-zero, the signal will be posted only to processes that have 113a controlling terminal. 114.Fn pgsignal 115is implemented by walking along the process list headed by the field 116.Li pg_members 117of the process group structure 118pointed at by 119.Fa pgrp 120and calling 121.Fn ksignal 122as appropriate. 123If 124.Fa pgrp 125is 126.Dv NULL 127no action is taken. 128.Pp 129The 130.Fn gsignal 131function posts signal number 132.Fa signum 133to each member of the process group identified by the group id 134.Fa pgid . 135.Fn gsignal 136first finds the group structure associated with 137.Fa pgid , 138then invokes 139.Fn pgsignal 140with the argument 141.Fa checkctty 142set to zero. 143If 144.Fa pgid 145is zero no action is taken. 146.Sh SEE ALSO 147.Xr sigaction 2 , 148.Xr tsleep 9 149