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SIGBLOCK(2)                 BSD System Calls Manual                SIGBLOCK(2)

     sigblock -- block signals

     Standard C Library (libc, -lc)

     #include <signal.h>

     sigblock(int mask);


     This interface is made obsolete by sigprocmask(2).

     Sigblock() adds the signals specified in mask to the set of signals currently being blocked from deliv-ery. delivery.
     ery.  Signals are blocked if the corresponding bit in mask is a 1; the macro sigmask() is provided to
     construct the mask for a given signum.

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

     The previous set of masked signals is returned.

     kill(2), sigaction(2), sigprocmask(2), sigsetmask(2), sigsetops(3)

     The sigblock() function call appeared in 4.2BSD and has been deprecated.

BSD                              June 2, 1993                              BSD

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