SIGSETOPS(3P)SIGSETOPS(3P)NAME
sigemptyset, sigfillset, sigaddset, sigdelset, sigismember - (POSIX
only) manipulate signal sets.
SYNOPSIS
#include <signal.h>
int sigemptyset(sigset_t *set);
int sigfillset(sigset_t *set);
int sigaddset(sigset_t *set, int signo);
int sigdelset(sigset_t *set, int signo);
int sigismember(const sigset_t *set, int signo);
DESCRIPTION
The information in this specification applies only to POSIX
applications.
The sigsetops primitives manipulate sets of signals. They operate on
data objects addressable by the application, not on any set of signals
known to the system, such as the set blocked from delivery to a process
or the set pending for a process.
The sigemptyset function initializes the signal set pointed to by the
argument set, such that all signals are excluded.
The sigfillset function initializes the signal set pointed to by the
argument set, such that all signals are included.
The sigaddset and sigdelset functions respectively add or delete the
individual signal specified by the value of the argument signo to or
from the signal set pointed to by the argument set.
The sigismember function tests whether the signal specified by the
value of the argument signo is a member of the set pointed to by the
argument set.
RETURNS
Upon successful completion, the sigismember function returns a value of
one if the specified signal is a member of the specified set, or a
value of zero if it is not. Upon successful completion, the other
functions return a value of zero. For all of the above functions, if
an error is detected, a value of -1 is returned, and errno is set to
indicate the error.
ERRORS
[EINVAL] The value of the signo argument is an invalid or
unsupported signal number.
SEE ALSOsigaction(2P), sigprocmask(2P)
August 1, 1992 SIGSETOPS(3P)