sigblock(3)        UNIX System V(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
























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