Re: silent semantic changes with reiser4

Jamie Lokier
2004-09-01T22:05:20Z

Pavel Machek wrote:
> > 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?

Granted, this is where we need "grep --recurse-into-files" or, more
generally useful, a find option.

> > 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.

There you go... a kernel hook to prepend /overlay works :)
These hook I keep mentioning, they are really very simple :)

> > 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?

Not if it's written properly.

-- Jamie