NAME

sigblock − block signals

SYNOPSIS

#include <signal.h>

oldmask = sigblock(mask);
int mask;

mask = sigmask(signum)

DESCRIPTION

Sigblock adds the signals specified in mask to the set of signals currently being blocked from delivery.  Signals are blocked if the corresponding bit in mask is a 1; the macro sigmask is provided to construct the mask for a given signum. The previous mask is returned, and may be restored using sigsetmask(2).

It is not possible to block SIGKILL, SIGSTOP, or SIGCONT;  this restriction is silently imposed by the system. 

RETURN VALUE

The previous set of masked signals is returned. 

SEE ALSO

kill(2), sigvec(2), sigsetmask(2), signal(3)

Sun Release 3.2  —  Last change: 16 July 1986