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SIGSETMASK(2) FreeBSD System Calls Manual SIGSETMASK(2)
NAME
sigsetmask, sigblock - manipulate current signal mask
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <signal.h>
int
sigsetmask(int mask);
int
sigblock(int mask);
int
sigmask(int signum);
DESCRIPTION
This interface is made obsolete by: sigprocmask(2).
The sigsetmask() function sets the current signal mask to the specified
mask. Signals are blocked from delivery if the corresponding bit in mask
is a 1. The sigblock() function adds the signals in the specified mask
to the current signal mask, rather than overwriting it as sigsetmask()
does. The macro sigmask() is provided to construct the mask for a given
signum.
The system quietly disallows SIGKILL or SIGSTOP to be blocked.
RETURN VALUES
The sigblock() and sigsetmask() functions return the previous set of
masked signals.
SEE ALSO
kill(2), sigaction(2), sigprocmask(2), sigsuspend(2), sigvec(2),
sigsetops(3)
HISTORY
The sigsetmask() and sigblock() functions first appeared in 4.2BSD and
have been deprecated.
FreeBSD 14.0-RELEASE-p11 June 2, 1993 FreeBSD 14.0-RELEASE-p11