> Indeed. Do you happen to have the complete traceback of the failing
> tempfile.mktemp() call? I don't see where it can use the PATH
> environment variable.

The problem was that somehow, on our systems, the TEMP environmental variable had been copied over with PATH. Most likely some batch file tried to store a copy of PATH, without realizing the significance of TEMP. [groan]

Anyway, I still think that it's a bug that abspath() can't be called with a perfectly good str path, because of limitations with the windows api. I edited the bug title to reflect the actual bug.

The str path length could be checked and upgraded to the Unicode version, if necessary (or try again with the unicode version, in the case of an exception). I think it's important to ensure that when abspath() is called with str, it returns str, even if it was upgraded to the unicode call.