[Xcb] knowing when the X server will send the reply

Peter Hutterer mailinglists at who-t.net
Mon Dec 31 19:05:45 PST 2007

Vincent Torri wrote:
> is it possible to know when the X server will send a reply ?

yes and no. the X server goes through the client requests one by one. 
some requests require a reply and the next request will not be processed 
until the reply has been sent.

if you send requests in a batch it is a bit more difficult. the sequence 
number of anything coming from the server tells you which request the 
server is currently at.
problem is if you send lots of request that don't have replies and no 
events happen you don't really know when the server will process your 

so you sort-of know when you'll get a reply but not really :)


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