1.\" Copyright (c) 1983, 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.\" @(#)sigsetops.3 8.1 (Berkeley) 6/4/93 29.\" 30.Dd October 29, 2019 31.Dt SIGSETOPS 3 32.Os 33.Sh NAME 34.Nm sigemptyset , 35.Nm sigfillset , 36.Nm sigaddset , 37.Nm sigandset , 38.Nm sigdelset , 39.Nm sigisemptyset , 40.Nm sigismember , 41.Nm sigorset 42.Nd manipulate signal sets 43.Sh LIBRARY 44.Lb libc 45.Sh SYNOPSIS 46.In signal.h 47.Ft int 48.Fn sigemptyset "sigset_t *set" 49.Ft int 50.Fn sigfillset "sigset_t *set" 51.Ft int 52.Fn sigaddset "sigset_t *set" "int signo" 53.Ft int 54.Fn sigandset "sigset_t *set" "const sigset_t *left" "const sigset_t *right" 55.Ft int 56.Fn sigdelset "sigset_t *set" "int signo" 57.Ft int 58.Fn sigisemptyset "const sigset_t *set" 59.Ft int 60.Fn sigismember "const sigset_t *set" "int signo" 61.Ft int 62.Fn sigorset "sigset_t *set" "const sigset_t *left" "const sigset_t *right" 63.Sh DESCRIPTION 64These functions manipulate signal sets stored in a 65.Fa sigset_t . 66Either 67.Fn sigemptyset 68or 69.Fn sigfillset 70must be called for every object of type 71.Fa sigset_t 72before any other use of the object. 73.Pp 74The 75.Fn sigemptyset 76function initializes a signal set to be empty. 77.Pp 78The 79.Fn sigfillset 80function initializes a signal set to contain all signals. 81.Pp 82The 83.Fn sigaddset 84function adds the specified signal 85.Fa signo 86to the signal set. 87.Pp 88The 89.Fn sigandset 90function sets the specified 91.Fa set 92to the logical AND of all signals from the 93.Fa left 94and 95.Fa right 96signal sets. 97.Pp 98The 99.Fn sigdelset 100function deletes the specified signal 101.Fa signo 102from the signal set. 103.Pp 104The 105.Fn sigisemptyset 106function returns whether the specified 107.Fa set 108is empty or not. 109.Pp 110The 111.Fn sigismember 112function returns whether a specified signal 113.Fa signo 114is contained in the signal set. 115.Pp 116The 117.Fn sigorset 118function sets the specified 119.Fa set 120to the logical OR of all signals from the 121.Fa left 122and 123.Fa right 124signal sets. 125.Sh RETURN VALUES 126The 127.Fn sigisemptyset 128function returns 1 129if the set is empty, 0 otherwise. 130.Pp 131The 132.Fn sigismember 133function returns 1 134if the signal is a member of the set, 1350 otherwise. 136.Pp 137The other functions return 0 upon success. 138A \-1 return value 139indicates an error occurred and the global variable 140.Va errno 141is set to indicate the reason. 142.Sh ERRORS 143These functions could fail if one of the following occurs: 144.Bl -tag -width Er 145.It Bq Er EINVAL 146.Fa signo 147has an invalid value. 148.El 149.Sh SEE ALSO 150.Xr kill 2 , 151.Xr sigaction 2 , 152.Xr sigpending 2 , 153.Xr sigprocmask 2 , 154.Xr sigsuspend 2 155.Sh STANDARDS 156The 157.Fn sigandset , 158.Fn sigisemptyset , 159and 160.Fn sigorset 161functions are FreeBSD extensions, compatible with functions of the same name 162provided by both musl libc and GNU libc. 163.Pp 164The rest of these functions are defined by 165.St -p1003.1-88 . 166