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

NAME
     sigblock -- block signals

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <signal.h>

     int
     sigblock(int mask);

     int
     sigmask(signum);

DESCRIPTION
     This interface is made obsolete by sigprocmask(2).

     Sigblock() adds the signals specified in mask to the set of signals cur-rently currently
     rently being blocked from delivery.  Signals are blocked if the corre-sponding corresponding
     sponding 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.

RETURN VALUES
     The previous set of masked signals is returned.

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

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

BSD                              June 2, 1993                              BSD