Wow, that's interesting!
Oh crap, I ran the code and it's not helpful, all files more than 8 chars are abbreviated.
That's how QB45 and the old DOS systems used to be limited with file names. 8 characters plus 3 for the extension. Windows will still work with those abbreviated file names -- if you can keep your programs straight with them!
Note how FILES only prints those names to your screen. You've got to read them back into your program from there, if you actually want to make use of them!!
Personally, I'll just stick with the cross-platform "direntry.h" method. ;)