SSIGNAL(3C)                                           SSIGNAL(3C)



     NAME
          ssignal, gsignal - software signals

     SYNOPSIS
          #include <signal.h>

          int (*ssignal (sig, action))( )
          int sig, (*action)( );

          int gsignal (sig)
          int sig;

     DESCRIPTION
          ssignal and gsignal implement a software facility similar to
          signal(2).  This facility is used by the Standard C Library
          to enable users to indicate the disposition of error
          conditions, and is also made available to users for their
          own purposes.

          Software signals made available to users are associated with
          integers in the inclusive range 1 through 16. A call to
          ssignal associates a procedure, action, with the software
          signal sig; the software signal, sig, is raised by a call to
          gsignal.  Raising a software signal causes the action
          established for that signal to be taken.

          The first argument to ssignal is a number identifying the
          type of signal for which an action is to be established. The
          second argument defines the action; it is either the name of
          a (user-defined) action function or one of the manifest
          constants SIGDFL (default) or SIGIGN (ignore).  ssignal
          returns the action previously established for that signal
          type; if no action has been established or the signal number
          is illegal, ssignal returns SIGDFL.

          Gsignal raises the signal identified by its argument, sig:

               If an action function has been established for sig,
               then that action is reset to SIGDFL and the action
               function is entered with argument sig.  Gsignal returns
               the value returned to it by the action function.

               If the action for sig is SIGIGN, gsignal returns the
               value 1 and takes no other action.

               If the action for sig is SIGDFL, gsignal returns the
               value 0 and takes no other action.

               If sig has an illegal value or no action was ever
               specified for sig, gsignal returns the value 0 and
               takes no other action.




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     SSIGNAL(3C)                                           SSIGNAL(3C)



     SEE ALSO
          signal(2), sigset(2).

     NOTES
          There are some additional signals with numbers outside the
          range 1 through 16 which are used by the Standard C Library
          to indicate error conditions.  Thus, some signal numbers
          outside the range 1 through 16 are legal, although their use
          may interfere with the operation of the Standard C Library.

     ORIGIN
          AT&T V.3











































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