Re: tiff multi-document files

[Alexander Larsson <alexl redhat com>]

On Tue, 2004-01-20 at 08:17, George Karabin wrote:
> On Jan 19, 2004, at 1:39 AM, Alexander Larsson wrote:
> 
> > On Sun, 2004-01-18 at 11:34, Jens Finke wrote:
> >> Actually, I think it should be possible to write a gnome-vfs module,  
> >> which
> >> adds a new URI scheme and handles such tiff files properly. If it  
> >> behaves
> >> like a directory from the gnome-vfs client point of view, eog will
> >> automatically use the collection view for this then.
> >
> > This is called "chained uris", and gnome-vfs has some code for it.
> > However, at the moment it just doesn't work. My hope is that eventually
> > we'll get it fixed though.
> 
> 
> I looked at the archives for this list on chaining and the shared vfs  
> ideas on xdg-list. Has anything come of your idea for a common VFS URI  
> spec:  
> https://listman.redhat.com/archives/xdg-list/2003-September/
> msg00110.html ? Do you think it makes any sense to attempt to fix  
> chaining before attempting such a spec?

There hasn't been any work on it that I know of. And in such a spec it
would be nice if chaining was supported.

> Regarding a VFS URI spec, I thought I'd go looking for relevant  
> internet standards and drafts, and note them here. They might make for  
> some good references for requirements gathering for anyone thinking  
> about such a spec.

In some sense its sort of unfortunate that gnome-vfs uris are based on
normal URIs, because that limits us a bit and in some cases it causes
trouble because people expect that gnome-vfs should support all sorts of
things you can do with web-uris, such as mailto:, callto:, javascript:
etc. In fact, we partially handle these by installing handler app
settings for them, but in reality they are not really gnome-vfs uris.

The way gnome-vfs currently handles chained uris is described in
gnome-vfs/doc/uri.txt. Its working to some extent, but the work has
never really been finalized and polished up to work in the desktop.

To make it work you'd have to:
* Work on the chained methods (zip, tar, gzip etc) to make them work
better than they do today. The existance of the gnome-vfs daemon in 2.5
should make this easier
* Finish the work with putting chained uri handlers into the mime info,
so that the file manager can now what file types are chainable
* Make the file handler recognize chainable file types and browse them
* Make all users of gnome-vfs correctly handle chained uris (i.e.
gnome_vfs_uri_get_parent() on file:///some/file#foo:/ returns
file:///some/file.)

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 Alexander Larsson                                            Red Hat, Inc 
                   alexl redhat com    alla lysator liu se 
He's an old-fashioned day-dreaming Green Beret possessed of the uncanny powers 
of an insect. She's a cold-hearted antique-collecting hooker married to the 
Mob. They fight crime!