This is almost not a ruby question... But I need a ruby solution!

How to convert a 8.3 dos paths to its fully expanded version. For
example, how to translate:

C:\\CYGWIN\\HOME\MYFULL~1\MONROE~9.ALT

to

/cygdrive/c/cygwin/home/My Full Name/Monroe-Tyson.alt

The basename of this last path is relevant to me and while MONROE~9 is
unusable. cygpath -u, from the cygwin distribution, doesn't expand the
8.3 names. It merely changes the \\ into /. How fancy!

Any solution out there?
Guillaume.