ssignal(3C) — sys5



SSIGNAL(3C)     DOMAIN/IX Reference Manual (SYS5)     SSIGNAL(3C)



NAME
     ssignal, gsignal - software signals

USAGE
     #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 allow you to specify how to dispose of error conditions.

     Software signals available to you are associated with
     integers in the inclusive range 1 through 15. 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 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 zero and takes no other action.

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

NOTES
     There are additional signals, with numbers outside the range



Printed 5/10/85                                         SSIGNAL-1



SSIGNAL(3C)     DOMAIN/IX Reference Manual (SYS5)     SSIGNAL(3C)



     1 through 15, which are used by the Standard C Library to
     indicate error conditions; these are defined in < signal.h
     >.  If you specify one of them, your program may interfere
     with the normal operation of the Standard C Library.

RELATED INFORMATION
     signal(2)
















































SSIGNAL-2                                         Printed 5/10/85

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