sigsetops(3C)

NAME

sigsetops, sigemptyset, sigfillset, sigaddset, sigdelset, sigismember − manipulate sets of signals

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(sigset_t ∗set, int signo);

DESCRIPTION

These functions manipulate sigset_t data types, representing the set of signals supported by the implementation.

sigemptyset() initializes the set pointed to by set to exclude all signals defined by the system.

sigfillset() initializes the set pointed to by set to include all signals defined by the system.

sigaddset() adds the individual signal specified by the value of signo to the set pointed to by set.

sigdelset() deletes the individual signal specified by the value of signo from the set pointed to by set.

sigismember() checks whether the signal specified by the value of signo is a member of the set pointed to by set.

Any object of type sigset_t must be initialized by applying either sigemptyset() or sigfillset() before applying any other operation.

RETURN VALUES

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 0 if it is not. Upon successful completion, the other functions return a value of 0. Otherwise a value of −1 is returned and errno is set to indicate the error.

ERRORS

sigaddset(), sigdelset(), and sigismember() will fail if the following is true:

EINVAL The value of the signo argument is not a valid signal number.

sigfillset will fail if the following is true:

EFAULT The set argument specifies an invalid address.

Museum