ssignal(3C)          COMPATIBILITY FUNCTIONS          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  esta-
     blished 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 con-
     stants  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).





          Last change: C Programming Language Utilities         1