NTFS has always been case sensitive, Windows API just lets you treat it as case insensitive. If you pass `FILE_FLAG_POSIX_SEMANTICS` to `CreateFile` you can make files that differ only in case.
Good luck using those in some tools which use the API differently though. Windows filenames are endless fun. What's the maximum length of the absolute path of a file? Why, that depends on which API you're using to access it!
Even worse on Unix where it depends on the mount type. Haven't seen much proper long filename support in Unix apps or libs, it's much better in Windows land. Garbage in garbage out is also a security nightmare as names are not identifiable anymore. You can easily spoof such names.
