When the attached program is run on Linux it runs "instantly" and
outputs one line, e.g.:

$ python3 mtest.py
100 files, 1702627142 bytes

(The number of bytes will vary depending on the system.)

When run on Windows XP there is no output at all; many processes seem to
be created but nothing seems to actually get done.

In both cases I'm using Py30b2.