NT 4.0 contains file system tunneling capabilities to allow for compatibility
with applications that rely on file systems being able to hold onto file
meta-info for a short period of time. This occurs after deletion or renaming and
re-introducing a new directory entry with that meta-info (if a create or rename
occurs to cause a file of that name to appear again in a short period of time).
The idea is to mimic the behavior DOS applications expect when they use the safe
save method. They copy the modified data to a temporary file, delete the
original and rename the temporary to the original. This should appear to be the
original file when complete. Windows NT performs tunneling on both FAT and NTFS
file systems to ensure long/short file names are retained when 16-bit
applications perform this safe save operation. See Q172190
