Re: silent semantic changes with reiser4

Pavel Machek
2004-09-01T20:18:24Z

Hi!

> > > It's not about the kernel, it's about the interface. And see my other mail:
> > > cat foo.zip/README
> > > less foo.zip/contents/bar.c
> > > is a lot easier than
> > > lynx http://google.com/search?q=zip
> > > emerge zip
> > > man zip
> > > unzip foo.zip
> > > cat bar.c
> > > which already assumes quite a lot of expertise.
> >
> > If you only want nice user interface, you can have that today. Its
> > done using coda, and hosted at uservfs.sf.net.
>
> Can I do these already using uservfs?
>
> cd
> less foo.zip/contents/bar.c

less foo.zip#uzip/contents/bar.c

> less /usr/portage/distfiles/perl-5.8.5.tar.gz/contents/toke.c

less /usr/portage/distfiles/perl-5.8.5.tar.gz#utar/contents/toke.c

> grep -R obscure_label ~/RPMS

I do not think you'd want this. How would you tell grep obscure label
without entering archives, then?

> No I can't.

> Even using the right "#" names for uservfs ('foo.zip#zip' etc.), I can
> only do the above with convenient paths, completion etc. if I mount
> my

Well, you can... or at least I had version somewhere that
automagically prepended /overlay when file was not found. That way,
normal requests were fast and uservfs were used whenever it was
needed... At the price of little uglyness and slowing down -ENOENTs.

> As we're adding file-as-directories to VFS, I propose it would be good
> to have *hooks* in place, and non-metadata namespace reserved inside
> the directories, so that uservfs-like userspace filesystems can
> be auto-mounted at those places and synchronised with the file.
>
> In other words, something that makes the next version of uservfs a
> whole lot more useful.

Yep, something less hacky would be nice.

> So all I am asking for is a facility to auto-mount with
> file-as-directory, and the ability for a userspace daemon to be
> notified of regular file modifications synchronously. Both can be
> added later, once file-as-directory and moveable mounts are

If the userspace daemon is synchronously notified of file
modification... will not that lead to very ugly deadlocks?
Pavel

--
Horseback riding is like software...
...vgf orggre jura vgf serr.