[Python-3000] Removal of os.path.walk

["Martin v. Löwis"]

> I don't know how compelling it is, but the dirread Plan 9 call to get
> a directory listing
> (http://plan9.bell-labs.com/magic/man2html/2/dirread) returns only a
> subset of the entries in the directory so it effectively acts as an
> iterator.

All operating system APIs to read directories work in this way;
Plan 9 is not unique (here).

> If it's listing a network shared file system an iterator
> version of listdir could result in less network traffic depending on
> what entry you were looking for.  I don't know if NFS is the same but
> I think in general it would be a win for network file systems in terms
> of efficiency.

Still, Guido's question stands: do you have an actual use case where
you would want to stop earlier? Even if you glob, you still need to
read to the end of the directory.

Regards,
Martin