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SIGSETOPS(3) FreeBSD Library Functions Manual SIGSETOPS(3)
NAME
sigemptyset, sigfillset, sigaddset, sigandset, sigdelset, sigisemptyset,
sigismember, sigorset - manipulate signal sets
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <signal.h>
int
sigemptyset(sigset_t *set);
int
sigfillset(sigset_t *set);
int
sigaddset(sigset_t *set, int signo);
int
sigandset(sigset_t *set, const sigset_t *left, const sigset_t *right);
int
sigdelset(sigset_t *set, int signo);
int
sigisemptyset(const sigset_t *set);
int
sigismember(const sigset_t *set, int signo);
int
sigorset(sigset_t *set, const sigset_t *left, const sigset_t *right);
DESCRIPTION
These functions manipulate signal sets stored in a sigset_t. Either
sigemptyset() or sigfillset() must be called for every object of type
sigset_t before any other use of the object.
The sigemptyset() function initializes a signal set to be empty.
The sigfillset() function initializes a signal set to contain all
signals.
The sigaddset() function adds the specified signal signo to the signal
set.
The sigandset() function sets the specified set to the logical AND of all
signals from the left and right signal sets.
The sigdelset() function deletes the specified signal signo from the
signal set.
The sigisemptyset() function returns whether the specified set is empty
or not.
The sigismember() function returns whether a specified signal signo is
The sigismember() function returns 1 if the signal is a member of the
set, 0 otherwise.
The other functions return 0 upon success. A -1 return value indicates
an error occurred and the global variable errno is set to indicate the
reason.
ERRORS
These functions could fail if one of the following occurs:
[EINVAL] signo has an invalid value.
SEE ALSO
kill(2), sigaction(2), sigpending(2), sigprocmask(2), sigsuspend(2)
STANDARDS
The sigandset(), sigisemptyset(), and sigorset() functions are FreeBSD
extensions, compatible with functions of the same name provided by both
musl libc and GNU libc.
The rest of these functions are defined by IEEE Std 1003.1-1988
("POSIX.1").
FreeBSD 14.0-RELEASE-p11 October 29, 2019 FreeBSD 14.0-RELEASE-p11