[Python-Dev] test_urllibnet failing on Windows

[Tim Peters]

[Guido]
> The test assumes that the fileno() from a socket object can be passed
> to os.fdopen().

Yup, Jeremy figured that out here.  I have a patch waiting to go, but SF
isn't cooperating.

> That works on Unix.  But on Windows it cannot, the small ints used to
> refer to open files are chosen from a different (though potentially
> overlapping) space than the small ints used to refer to open sockets,
> and the two cannot be mixed.

Just so.

> So the test should be disabled on Windows.
>
> I don't know if we can protect os.fdopen() from crashing when passed
> an out of range number.

This is an issue only in the MSVC debug build.  The release-build MS
libraries *still* explicitly check for out-of-range, and arrange for an
error return when it is out of range.  I really don't understand why they're
asserting in-range in their debug build libraries, because nothing in
*their* code assumes the fd is in-range -- their code is defensive enough in
the release build that nothing bad will happen even when it is out of range.