XPutBackEvent - put events back on the queue
Specifies the connection to the X server.
Specifies the event.
function pushes an event back onto
the head of the display's event queue by copying the event into the queue.
This can be useful if you read an event and then decide that you would rather
deal with it later. There is no limit to the number of times in succession
that you can call
XAnyEvent(3X11), XIfEvent(3X11), XNextEvent(3X11), XSendEvent(3X11)
Xlib -- C Language X Interface