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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	1.6.5			     XFlush(3)

NAME | SYNTAX | ARGUMENTS | DESCRIPTION | SEE ALSO

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