[Xcb] zeroing out

Barton C Massey bart at cs.pdx.edu
Fri Dec 30 23:02:14 PST 2005


Sounds like in principle, significant null bytes could
appear in some count/chars strings sent by the X server.  In
practice I would be shocked, but that's standards for you.

What we probably want is a few convenience functions in XCB
for dealing with these things, like the nstrcmp() [horrible
name, maybe not right API] I wrote for xcbxvinfo.  I'm not
sure what else to do, really...

	Bart

In message <Pine.LNX.4.44.0512302159230.20006-100000 at diane.unet.brandeis.edu> you wrote:
> On Fri, 30 Dec 2005, Keith Packard wrote:
> 
> > On Fri, 2005-12-30 at 16:49 -0800, Barton C Massey wrote:
> > 
> > > Anyone remember offhand whether null bytes are allowed in
> > > the count/chars strings returned by X requests?  Anyone know
> > > whether there must be a space in the reply for a trailing
> > > null byte?  If either of these things are wrong, then XCB
> > > isn't reasonably going to be able to return C strings...
> > 
> > Strings in X replies are not nul terminated. Xlib allocates an extra
> > byte for 8-bit properties and stuffs a nul in there.
> > 
> > -keith
> > 
> > 
> 
> Is there any reason we would not need to return a NULL terminated string?  
> It seems like that is something we should provide to prevent a lot of 
> duplicated code client side.
> 
> Jeremy


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