Archives and magic bytes

> Perhaps this is mostly a reflection on me as a programmer :-} but I> found the job surprisingly tricky.
No I think you're right...
It's not very important for me retrieve exactly what kind of file it
is, it could be just something more in my little program (an organizer
that put files in the right directories using extensions of files,
categories and regular expressions).

A really good file identifier is this one(the author is a friend of mine):
http://mark0.net/soft-trid-e.html

It doesn't work with mono yet but maybe one day I'll try to use it
with python...

Thanks everybody