This partially reverts 991e4404e910, because the URL form of C:\... gets
escaped to C%3A/..., which breaks the substitution of $TESTTMP.
The forget command on 'notafile*' errored out with:
notafile*: The filename, directory name, or volume label syntax is incorrect
which I think is because '*' isn't a legal character in a file name (though I
can't trigger this directly from MSYS or cmd.exe for some reason).