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.Dd October 29, 2019 29.Dt SIGSETOPS 3 30.Os 31.Sh NAME 32.Nm sigemptyset , 33.Nm sigfillset , 34.Nm sigaddset , 35.Nm sigandset , 36.Nm sigdelset , 37.Nm sigisemptyset , 38.Nm sigismember , 39.Nm sigorset 40.Nd manipulate signal sets 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.In signal.h 45.Ft int 46.Fn sigemptyset "sigset_t *set" 47.Ft int 48.Fn sigfillset "sigset_t *set" 49.Ft int 50.Fn sigaddset "sigset_t *set" "int signo" 51.Ft int 52.Fn sigandset "sigset_t *set" "const sigset_t *left" "const sigset_t *right" 53.Ft int 54.Fn sigdelset "sigset_t *set" "int signo" 55.Ft int 56.Fn sigisemptyset "const sigset_t *set" 57.Ft int 58.Fn sigismember "const sigset_t *set" "int signo" 59.Ft int 60.Fn sigorset "sigset_t *set" "const sigset_t *left" "const sigset_t *right" 61.Sh DESCRIPTION 62These functions manipulate signal sets stored in a 63.Fa sigset_t . 64Either 65.Fn sigemptyset 66or 67.Fn sigfillset 68must be called for every object of type 69.Fa sigset_t 70before any other use of the object. 71.Pp 72The 73.Fn sigemptyset 74function initializes a signal set to be empty. 75.Pp 76The 77.Fn sigfillset 78function initializes a signal set to contain all signals. 79.Pp 80The 81.Fn sigaddset 82function adds the specified signal 83.Fa signo 84to the signal set. 85.Pp 86The 87.Fn sigandset 88function sets the specified 89.Fa set 90to the logical AND of all signals from the 91.Fa left 92and 93.Fa right 94signal sets. 95.Pp 96The 97.Fn sigdelset 98function deletes the specified signal 99.Fa signo 100from the signal set. 101.Pp 102The 103.Fn sigisemptyset 104function returns whether the specified 105.Fa set 106is empty or not. 107.Pp 108The 109.Fn sigismember 110function returns whether a specified signal 111.Fa signo 112is contained in the signal set. 113.Pp 114The 115.Fn sigorset 116function sets the specified 117.Fa set 118to the logical OR of all signals from the 119.Fa left 120and 121.Fa right 122signal sets. 123.Sh RETURN VALUES 124The 125.Fn sigisemptyset 126function returns 1 127if the set is empty, 0 otherwise. 128.Pp 129The 130.Fn sigismember 131function returns 1 132if the signal is a member of the set, 1330 otherwise. 134.Pp 135The other functions return 0 upon success. 136A \-1 return value 137indicates an error occurred and the global variable 138.Va errno 139is set to indicate the reason. 140.Sh ERRORS 141These functions could fail if one of the following occurs: 142.Bl -tag -width Er 143.It Bq Er EINVAL 144.Fa signo 145has an invalid value. 146.El 147.Sh SEE ALSO 148.Xr kill 2 , 149.Xr sigaction 2 , 150.Xr sigpending 2 , 151.Xr sigprocmask 2 , 152.Xr sigsuspend 2 153.Sh STANDARDS 154The 155.Fn sigandset , 156.Fn sigisemptyset , 157and 158.Fn sigorset 159functions are FreeBSD extensions, compatible with functions of the same name 160provided by both musl libc and GNU libc. 161.Pp 162The rest of these functions are defined by 163.St -p1003.1-88 . 164