> I'm probably missing something, but I don't see why this problem can't be
> solved in user space. [...]
nope this doesnt work, as Linus has already noted, theoretically the
conversion is an exponentially bad backoff algorithm, not good. My
assumption (that MSDOS is 'nonescaping') was trivially wrong,
'/dos/win/temp/../TEMP/../../TMP' is just one counter example. Filenames
might go in and out of filesystems, and you dont really know how to
resolve the conflict in user-space: you'd need to pass back _where_ the
lookup failed to make it at least linear (still not too nice), this
clearly cannot be solved via flags. User-space is just too far in this
case, lets forget about putting generic lookup solutions there. [without
extending the API that is]. And even by putting it into user-space the
problem remains largely unsolved ...
-- mingo