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XFlush(3)			XLIB FUNCTIONS			     XFlush(3)

NAME
       XFlush,	XSync, XEventsQueued, XPending - handle	output buffer or event
       queue

SYNTAX
       int XFlush(Display *display);

       int XSync(Display *display, Bool	discard);

       int XEventsQueued(Display *display, int mode);

       int XPending(Display *display);

ARGUMENTS
       discard	 Specifies a Boolean value that	indicates whether  XSync  dis-
		 cards all events on the event queue.

       display	 Specifies the connection to the X server.

       mode	 Specifies the mode.  You can pass QueuedAlready, QueuedAfter-
		 Flush,	or QueuedAfterReading.

DESCRIPTION
       The XFlush function flushes the output buffer.	Most  client  applica-
       tions need not use this function	because	the output buffer is automati-
       cally flushed as	needed by calls	to XPending, XNextEvent, and  XWindow-
       Event.	Events	generated  by  the server may be enqueued into the li-
       brary's event queue.

       The XSync function flushes the output buffer and	then waits  until  all
       requests	 have been received and	processed by the X server.  Any	errors
       generated must be handled by the	error handler.	For each protocol  er-
       ror  received  by Xlib, XSync calls the client application's error han-
       dling routine (see section 11.8.2).  Any	events generated by the	server
       are enqueued into the library's event queue.

       Finally,	 if you	passed False, XSync does not discard the events	in the
       queue.  If you passed True, XSync discards all events in	the queue, in-
       cluding	those  events  that were on the	queue before XSync was called.
       Client applications seldom need to call XSync.

       If mode is QueuedAlready, XEventsQueued returns the  number  of	events
       already in the event queue (and never performs a	system call).  If mode
       is QueuedAfterFlush, XEventsQueued returns the number of	events already
       in  the	queue if the number is nonzero.	 If there are no events	in the
       queue, XEventsQueued flushes the	output buffer, attempts	to  read  more
       events  out  of	the  application's  connection,	and returns the	number
       read.  If mode is QueuedAfterReading, XEventsQueued returns the	number
       of  events already in the queue if the number is	nonzero.  If there are
       no events in the	queue, XEventsQueued attempts to read more events  out
       of  the application's connection	without	flushing the output buffer and
       returns the number read.

       XEventsQueued always returns  immediately  without  I/O	if  there  are
       events  already in the queue.  XEventsQueued with mode QueuedAfterFlush
       is  identical  in  behavior  to	XPending.   XEventsQueued  with	  mode
       QueuedAlready is	identical to the XQLength function.

       The  XPending  function returns the number of events that have been re-
       ceived from the X server	but have  not  been  removed  from  the	 event
       queue.	 XPending   is	 identical  to	XEventsQueued  with  the  mode
       QueuedAfterFlush	specified.

SEE ALSO
       AllPlanes(3), XIfEvent(3), XNextEvent(3), XPutBackEvent(3)
       Xlib - C	Language X Interface

X Version 11			 libX11	1.6.12			     XFlush(3)

NAME | SYNTAX | ARGUMENTS | DESCRIPTION | SEE ALSO

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