XFlush(3X11)                X Version 11(Release 5)                XFlush(3X11)


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

SYNTAX
      XFlush(display)
            Display *display;

      XSync(display, discard)
            Display *display;
            Bool discard;

      int XEventsQueued(display, mode)
           Display *display;
           int mode;

      int XPending(display)
            Display *display;

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

      display   Specifies the connection to the X server.

      mode      Specifies the mode.  You can pass QueuedAlready,
                QueuedAfterFlush, or QueuedAfterReading.

DESCRIPTION
      The XFlush function flushes the output buffer.  Most client applications
      need not use this function because the output buffer is automatically
      flushed as needed by calls to XPending, XNextEvent, and XWindowEvent.
      Events generated by the server may be enqueued into the library'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 error
      received by Xlib, XSync calls the client application's error handling
      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,
      including 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


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XFlush(3X11)                X Version 11(Release 5)                XFlush(3X11)


      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
      received 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(3X11), XIfEvent(3X11), XNextEvent(3X11), XPutBackEvent(3X11)
      Xlib - C Language X Interface


































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