Re: GTK frame changes

["Jan Djärv" <jan.h.d@swipnet.se>]

grischka skrev:
> Jan Djärv wrote:
>> grischka skrev:
>>> Jan Djärv wrote:
>>>> XSync sends a request to the server and waits for a reply.  The resize
>>>> request is sent before that, so the resize should be handeled before 
>>>> the XSync reply is sent.
>>>
>>> Yes, but this reply is something in the sense of the X protocol, not
>>> in the sense of ConfigureNotify.  It just means that the X server got
>>> the resize message when XSync returns.   It doesn't mean at all that
>>> a ConfigureNotify is already in the client queue let alone that emacs
>>> now knows how big it is.
>>>
>>
>> The XProtocol specification (the oldest I have is R6.8, the newest is 
>> 7.4, they say the same thing) says this:
>>
>> "Whether or not a server is implemented with internal concurrency,
>> the overall effect must be as if individual requests are executed to 
>> completion in some serial order,
>> and requests from a given connection must be executed in delivery order
>> (that is, the total execution order is a shuffle of the individual 
>> streams).
>> The execution of a request includes validating all arguments,
>> collecting all data for any reply,
>> and generating and queueing all required events.
>> However, it does not include the actual transmission of the reply and 
>> the events.
>> In addition, the effect of any other cause that can generate multiple 
>> events
>> (for example, activation of a grab or pointer motion) must effectively 
>> generate and queue all required events indivisibly with respect to all 
>> other causes and requests.
>>
>> For a request from a given client,
>> any events destined for that client that are caused by executing the 
>> request
>> must be sent to the client before any reply or error is sent."
> 
> I'm somehow confused what they mean by reply here.  If events are sent
> before replies then replies must be something else.

Some X requests have replies from the server (like XCreatePixmap, the reply 
contains the Pixmap id), some don't (like XFreePixmap).

> 
>> I interpret this as for a given X connection, all requests are run to 
>> completion and replies and events are queued in order.  Since XSync 
>> waits for the reply, it also means that after XSync has returned, 
>> events and replies generated by previous requests have indeed arrived.
> 
> Okay, I tested once more with an undecorated window and there indeed it
> looks like your interpretation might be right.
> 
> Just with WM redirection (metacity here) the ConfigureNotify clearly 
> arrives
> about 2 ms later and the behavior is completely unimpressed by XSync.
> 

With redirections all bets are off, since the X server can't know when or if 
there will be a reply.

	Jan D.