Message 81093 - Python tracker

As for checking CRT handles: it seems that __pioinfo is exported from
msvcr90.dll. So we could check whether osfile has the FOPEN flag set,
and we could check whether fh >= 0. Unfortunately, there seems to be no
way to check for _nhandle. However, that might not be necessary: IIUC,
we just need to check whether M=fh>>IOINFO_L2E is smaller than
IOINFO_ARRAYS and __pioinfo[M] is not null.