SIGBLOCK(2)         Linux Programmer's Manual         SIGBLOCK(2)

NAME
       sigblock, siggetmask, sigsetmask, sigmask - manipulate the
       signal mask

SYNOPSIS
       #include <signal.h>

       int sigblock(int mask);

       int siggetmask(void);

       int sigsetmask(int mask);

       int sigmask(int signum);

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

       The sigblock system call adds  the  signals  specified  in
       mask  to  the  set of signals currently being blocked from
       delivery.

       The sigsetmask system call replaces  the  set  of  blocked
       signals totally with a new set specified in mask.  Signals
       are blocked if the corresponding bit in mask is a 1.

       The current set of blocked signals can be  obtained  using
       siggetmask.

       The  sigmask macro is provided to construct the mask for a
       given signum.

RETURN VALUES
       siggetmask returns the current set of masked signals.

       sigsetmask and sigblock return the previous set of  masked
       signals.

NOTES
       Prototypes  for  these  functions  are  only  available if
       __USE_BSD is defined before <signal.h> is included.

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

CONFORMING TO
       4.4BSD.  These  function calls appeared in BSD 4.3 and are
       deprecated.  Use the POSIX signal facilities for new  pro-
       grams.

SEE ALSO
       kill(2), sigprocmask(2), signal(7)

Linux 1.3                 31 August 1995                        1