There seems to be a problem with fdopen() when it operates on the file handle returned by _open_osfhandle.  When the following code fragment runs, it generates a "Bad file descriptor" error.  The fhandle value seems to be correct (in this case, it's a 4).

    fhandle = _open_osfhandle( InputHandle, O_RDONLY );
    file  = fdopen( fhandle, "r" );