NAME

sigdelset — delete a signal from a signal set

SYNOPSIS

#include <signal.h>

int sigdelset(sigset_t *set, int signo);

DESCRIPTION

The sigdelset() function deletes the individual signal specified by signo from the signal 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, sigdelset() returns 0. Otherwise, it returns -1 and sets errno to indicate the error.

ERRORS

The sigdelset() 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) , sigemptyset(3) , sigfillset(3) , sigismember(3) , sigpending(3) , sigprocmask(3) , sigsuspend(3) , <signal.h> .

DERIVATION

Derived from the POSIX.1-1988 standard.