[Xcb] xcb and protocol versions
mailinglists at who-t.net
Thu Feb 22 15:17:02 PST 2007
On 23/02/2007, at 05:48 , Jeremy A. Kolb wrote:
> I am unsure how to handle the case where the client uses a
> request from an older version of the extension that has now changed
> signature in a later version of xcb.
don't change it. If you decide to fill existing padding fields with
data, that is fine because the client won't access them. if you start
adding bytes, you will most likely get the client out of sync.
there's probably some stuff you can do with fake padding. say you
have a request with a length field and a count variable. count gives
you the number of bytes after the 32 standard. you could change
length but not count, resulting in fake padding bytes being added at
the end. for newer versions, you can then stuff data in there. not
sure it's wise to go there though.
If you want to extend a request, you have to have version negotiation
and send back exactly what the client wants, depending on the version
the client is running.
Multi-Pointer X Server
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