NAME

sigblock − block signals

SYNOPSIS

oldmask = sigblock(mask);
int mask;

DESCRIPTION

Sigblock adds the signals specified in mask to the set of signals currently being blocked from delivery.  Signal i is blocked if the i−1’th bit in mask is a 1.  That is, to block SIGINT use sigblock((1<<(SIGINT-1)).  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 3.0β  —  Last change: 4 January 1984