Page:Xlib - C Language X Interface.pdf/21

 Both extract the full serial number of the last request known by Xlib to have been processed by the X server. Xlib automatically sets this number when replies, events, and errors are received.

Both extract the full serial number that is to be used for the next request. Serial numbers are maintained separately for each display connection.

Both return the major version number (11) of the X protocol associated with the connected display.

Both return the minor protocol revision number of the X server.