ssignal(3C)         (C Programming Language Utilities)          ssignal(3C)


   NAME
         ssignal, gsignal - software signals

   SYNOPSIS
         #include <signal.h>

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

         int gsignal (int sig);

   DESCRIPTION
         ssignal and gsignal implement a software facility similar to
         signal(2).  This facility is made available to users for their own
         purposes.

         Software signals made available to users are associated with integers
         in the inclusive range 1 through 17. 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.

   SEE ALSO
         signal(2), sigset(2), raise(3C).






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