[Xcb] Porting the rest of the X.Org apps to xcb

[Rémi Denis-Courmont]

----- Message d'origine -----
> > Keeping in mind that things like GTK, Qt
> > and the likes are intended to *hide* the underlying windowing system, most
> > out there applications do not actually use Xlib directly at all.
>
> Unfortunately, a lot of the toolkits exposed Xlib API so that apps could do
> things that the toolkits didn't directly support, like setting EMWH properties
> before the toolkits got there or calling new/uncommon X extensions.

You will always find counter examples. Still, I expect the most common X11 "leak" is the X window ID for embedding (videos, OpenGL windows, X11 EMBED plugins, etc). The good news is that 32 bits integer do not depend on the library, XCB or Xlib.

Unfortunately, many libraries expose X11 in their API. However commonly used the affected functions are, breaking the API compatibility is a tough sell. GLX is perhaps the worse case. But Qt4 does it too, and I bet GTK as well.