NAME

sigismember — test for a signal in a signal set

SYNOPSIS

#include <signal.h>

int sigismember(const sigset_t *set, int signo);

DESCRIPTION

The sigismember() function tests whether the signal specified by signo is a member of the set pointed to by set .

Applications should call either sigemptyset() or sigfillset() at least once for each object of type sigset_t prior to any other use of that object. If such an object is not initialised in this way, but is nonetheless supplied as an argument to any of sigaction(), sigaddset(), sigdelset(), sigismember(), sigpending() or sigprocmask(), the results are undefined.

RETURN VALUE

Upon successful completion, sigismember() returns 1 if the specified signal is a member of the specified set, or 0 if it is not. Otherwise, it returns -1 and sets errno to indicate the error.

ERRORS

The sigismember() function may fail if:

[EINVAL]

The signo argument is not a valid signal number, or is an unsupported signal number.

EXAMPLES

None.

APPLICATION USAGE

None.

FUTURE DIRECTIONS

None.

SEE ALSO

sigaction(3) , sigaddset(3) , sigdelset(3) , sigfillset(3) , sigemptyset(3) , sigpending(3) , sigprocmask(3) , sigsuspend(3) , <signal.h> .

DERIVATION

Derived from the POSIX.1-1988 standard.