bionic (2) sigblock.2freebsd.gz

Provided by: freebsd-manpages_11.1-3_all bug

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.