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Tk_CreateClientMessageHandlerTk)Library	ProcedTk_CreateClientMessageHandler(3)

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NAME
       Tk_CreateClientMessageHandler,  Tk_DeleteClientMessageHandler  -	 asso-
       ciate procedure callback	with ClientMessage type	X events

SYNOPSIS
       #include	<tk.h>

       Tk_CreateClientMessageHandler(proc)

       Tk_DeleteClientMessageHandler(proc)

ARGUMENTS
       Tk_ClientMessageProc *proc (in)		 Procedure to invoke  whenever
						 a  ClientMessage  X event oc-
						 curs on any display.
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DESCRIPTION
       Tk_CreateClientMessageHandler arranges for proc to be  invoked  in  the
       future  whenever	 a ClientMessage X event occurs	that is	not handled by
       WM_PROTOCOL.  Tk_CreateClientMessageHandler is intended for use by  ap-
       plications which	need to	watch X	ClientMessage events, such as drag and
       drop applications.

       The callback to proc will be made  by  Tk_HandleEvent;  this  mechanism
       only  works in programs that dispatch events through Tk_HandleEvent (or
       through	other  Tk  procedures  that  call  Tk_HandleEvent,   such   as
       Tcl_DoOneEvent or Tk_MainLoop).

       Proc should have	arguments and result that match	the type Tk_ClientMes-
       sageProc:
	      typedef int Tk_ClientMessageProc(
		      Tk_Window	tkwin,
		      XEvent *eventPtr);
       The tkwin parameter to proc is the Tk window which is  associated  with
       this event.  EventPtr is	a pointer to the X event.

       Whenever	 an  X ClientMessage event is processed	by Tk_HandleEvent, the
       proc is called if it was	not handled  as	 a  WM_PROTOCOL.   The	return
       value  from proc	is normally 0.	A non-zero return value	indicates that
       the event is not	to be handled further; that is,	proc has done all pro-
       cessing that is to be allowed for the event.

       If  there are multiple ClientMessage event handlers, each one is	called
       for each	event, in the order in which they were established.

       Tk_DeleteClientMessageHandler may be called to delete a previously-cre-
       ated ClientMessage event	handler: it deletes each handler it finds that
       matches the proc	argument.  If no such handler exists, then  Tk_Delete-
       ClientMessageHandler  returns without doing anything.  Although Tk sup-
       ports it, it's probably a bad idea to have more than one	callback  with
       the same	proc argument.

KEYWORDS
       bind, callback, event, handler

Tk				      8.4     Tk_CreateClientMessageHandler(3)

NAME | SYNOPSIS | ARGUMENTS | DESCRIPTION | KEYWORDS

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