(BSD System Compatibility)

sigblock(3bsd)

sigblock, sigmask -- (BSD) block signals

Synopsis

   /usr/ucb/cc [flag . . . ] file . . .
   
   #include <signal.h>
   

   sigblock(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(3bsd).

It is not possible to block SIGKILL, SIGSTOP, or SIGCONT; this restriction is silently imposed by the system.

Return values

The previous set of masked signals is returned.

References

kill(2), sigaction(2), signal(2), sigsetmask(3bsd), sigvec(3bsd)