sigblock(3)             (BSD Compatibility Package)             sigblock(3)


   NAME
         sigblock, sigmask - block signals

   SYNOPSIS
         cc [ flag... ] file ... -lucb

         #include <signal.h>

         sigblock(mask);
         int mask;

         #define 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
         appropriate 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(3).

         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
         sigsetmask(2), sigvec(2)

         kill(2), sigaction(2), signal(2) in the Programmer's Reference
         Manual.






















   7/91                                                                 Page 1