[Xcb] xcb_aux_sync explained?

[Barton C Massey]

This is the same methodology that Xlib uses underneath to
sync.  For any request that returns a reply, you are
guaranteed that the request has been processed (and
therefore the connection "synced") when the reply arrives,
since the X server returns the replies in order.

get_input_focus is just used because it is mostly innocuous.
It is kind of hard on poor Eamon, since the SELinux bits
really don't want to let just anyone find out the input
focus since it leaks information.  But X didn't provide a
noop request with a reply, which is what is really needed
here, and it's really much much too late to fix that in any
backward-compatible way now.

	Bart

In message <20080806100402.GC9693 at abydos.adm.naquadah.org> you wrote:
> I wonder why/how this works:
> 
> void=20
> xcb_aux_sync (xcb_connection_t *c)
> {
>     free(xcb_get_input_focus_reply(c, xcb_get_input_focus(c), NULL));
> }
> 
> Any pointer? Anyone knows?