Re: Meta-info on files

["Ben 'The Con Man' Kahn" <xkahn mail cybersites com>]

On 21 Apr 1998, Russell Nelson wrote:

> Everybody seems to want meta-info on files.  I propose this plan
> (which, regardless of its merits, is at least New!  Different!  On
> Sale at your Local Grocer's Now!):
> 
> There's a library for dealing with file types.  Ordinarily, the
> library identifies files two ways: One, it looks them up in
> /usr/lib/magic.  If the file is a known type, it gets assigned a MIME
> type.  There's a lookup table which assigns properties (icon, viewer,
> editor, whatever) to the MIME types.  That's easy enough, and 90% of
> it is there.  The other method is to look up the filename in a
> database and assign MIME types that way.  That way, *.g3 files get
> identified as fax files, since they don't have a magic number.  And
> programs, which would otherwise get a generic "executable" icon, could 
> be assigned individual icons.  And files in /var/spool/fax/incoming
> would be identified as faxes even without a g3 extension.
> 
> The NewDifferent part is to create a new file type (call it, say,
> GnomePack, with a .gp extension) with a new magic number.  When a
> GnomePack-cognizent application loads up a GnomePack file, it knows
> that there is a resource fork and a data fork.  Any items in the
> resource fork override the properties which would otherwise comes from
> the MIME properties table.
> 
> Obviously, this works great across NFS, FTP, HTTP, and generic Unix
> filesystems.  It works great with all file manipulation packages, cp,
> mv, ln, tar, cpio (etc).  It doesn't work transparently from
> application to application.  However, that isn't a killer, because we
> don't have to be stupid about it.  The headers can be text instead of
> binary.  So, text editors will deal, if the users are just barely
> smart enough to leave the headers alone.  And we can have a pair of
> programs, ungp and regp which remove and create the header.  And
> gnome-libs can have "readdatafile" and "writedatafile" functions which 
> take care of removing/creating the headers.

	So a gnome application would have this text header?  So this would
be a small shell script?  Does that mean that the internal application
will have to be unpacked from the file to be run?

						-Ben

------------------------------------ |\      _,,,--,,_  ,) ----------
Benjamin Kahn                        /,`.-'`'   -,  ;-;;'
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 If you love something, write it in C; if it compiles, it is yours; 
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