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XtAppAddSignal(3)		 XT FUNCTIONS		     XtAppAddSignal(3)

NAME
       XtAppAddSignal, XtRemoveSignal, XtNoticeSignal -	register and remove a
       signal source

SYNTAX
       #include	<X11/Intrinsic.h>

       XtSignalId XtAppAddSignal(XtAppContext app_context, XtSignalCallback-
	      Proc proc, XtPointer client_data);

       void XtRemoveSignal(XtSignalId id);

       void XtNoticeSignal(XtSignalId id);

ARGUMENTS
       app_context
		 Specifies the application context.

       client_data
		 Specifies the argument	that is	to be passed to	the specified
		 procedure when	a signal has been raised.

       id	 Specifies the ID returned from	the corresponding XtAppAdd-
		 Signal	call.

       proc	 Specifies the procedure that is to be called when the signal
		 has been raised.

DESCRIPTION
       The XtAppAddSignal function initiates a mechanism for handling signals
       within the context of the Intrinsics.  Prior to establishing an operat-
       ing system dependent signal handler the application may call XtAppAdd-
       Signal and store	the returned id	in a place accessible to the signal
       handler.

       Upon receipt of a signal	from the operating system, the application may
       call XtNoticeSignal passing the id returned by the call to XtAppAdd-
       Signal.

       XtNoticeSignal is the only Intrinsics function that can safely be
       called from a signal handler.  If XtNoticeSignal	is called multiple
       times before the	Intrinsics are able to invoke the registered callback,
       the callback is only called once.  Logically the	Intrinsics maintain
       "pending" for each registered callback.	This flag is initially False
       and is set to True by XtNoticeSignal; the Intrinsics invoke the call-
       back whenever the flag is True, and the flag is set to False just be-
       fore the	callback is invoked.

       The XtRemoveSignal function is called to	remove the specified Intrin-
       sics signal handler.  The client	should disable the source of the sig-
       nal before calling XtRemoveSignal.

SEE ALSO
       XtAppAddTimeOut(3),XtAppAddInput(3),XtAppAddWorkProc(3)
       X Toolkit Intrinsics - C	Language Interface
       Xlib - C	Language X Interface

X Version 11			  libXt	1.2.0		     XtAppAddSignal(3)

NAME | SYNTAX | ARGUMENTS | DESCRIPTION | SEE ALSO

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