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SEUL: File formats and /etc/magic

> Not necessarily.  Joe developer writes an application for himself,
> suppose.  Why should he use a magic number?  Good programming practice,
> yes, but maybe he's the sort that likes lots of untyped pointers and
> goto's and doesn't want to do it.  There's nothing magical about magic
> numbers (erm...)  What I'm saying is that, technically, there's no reason
> for a given file to necessarily have a magic number.  The fact that most
> do is very nice, but does anyone know of any apps whose files might not be
> so well behaved?

However, if you look through the magic file, you'll find that many formats 
are detected not by a magic number, but by the actual format of the data.  
This means that, if you understand the format well enough, *any* file can be 
id'd.  The project I referred to (check www.ccil.org/~esr/ for a link) 
appears to be developing a better format/language for the magic file that is 
capable of detecting almost *anything*.

Besides, if someone writes a program that uses a non-id'able file format, it 
won't be go in SEUL without some changes.

Eventually we may have to define the "10 Commandments" for projects to follow 
before they can be integrated into SEUL.  It'll be more than 10, though.  For 
an example of this, check the guidelines for the GNOME project.

     Erik Walthinsen <omega@seul.org> - SEUL Project system architect
       /  \                SEUL: Simple End-User Linux -
      |    | M E G A            Creating a Linux distribution
      _\  /_                         for the home or office user