On Wed, 2010-10-20 at 11:34 +0200, Eirik Byrkjeflot Anonsen wrote: > What guarantees does X give when it comes to the order of events > generated in relation to processing of the requests sent by the client? > > (Also, of course: To which degree does various implementations of X > actually fulfill these guarantees?) > > > Some specific questions: > > X events have a "serial" value. I expect that any event delivered by X > will reflect the state after the request number "serial" (and all > preceding requests) have been processed. Is this correct?
Yes. > Can I also assume that the X event will reflect the state before any > requests with a later serial number is processed? > > (And I assume that "serial" is monotonically increasing, except on > wrap-arounds...) > > > > Context: > > Given an application that frequently performs a sequence of XCopyArea() > calls on the contents of a window. When this application receives > Expose events or GraphicsExpose events, it is necessary for the > application to know exactly which XCopyArea calls have taken effect to > be able to correctly calculate which area of the window has become > invalid. Yes, any X application that handles scrolling correctly and efficiently will be making these types of calculations. - Owen _______________________________________________ [email protected]: X.Org support Archives: http://lists.freedesktop.org/archives/xorg Info: http://lists.freedesktop.org/mailman/listinfo/xorg Your subscription address: [email protected]
