Re: silent semantic changes with reiser4

Denis Vlasenko
2004-08-26T14:01:59Z

On Thursday 26 August 2004 14:16, Christer Weinigel wrote:
> Spam <spam@tnonline.net> writes:
> > Keeping stuff in the kernel should make the new features
> > transparent to the applications.
>
> No, it will make just one special case, rename within the same
> filesystem, work. (Well, two special cases, rm will also delete
> the other forks).

In traditional UNIX filesystems, copy loses some info too
(owner,group,mode bits). cp and tar was taught about this
and they now can preserve that info.

However, I do not think that hacking on cp, tar, etc everytime
we need to add something to our filesystems (xattrs, ACLs,
whatever) is a terribly attractive idea.

I think reiserfs is going to handle that by giving uniform access
to such ancillary data. It will be visible as file/meta/*
filelets ('small files') or something like that and can be saved/restored
by e.g. tar *without* needing to know what data is stored there, and
in what format.

I think Hans is not planning turning old "file is a stream of bytes"
into eight-stream octopus. One stream will remain as a 'main' one,
which contains actual data. Others will keep metadata, etc...

Note that even today's files aren't simple "streams of bytes"
because they also have names,mode bits etc.
--
vda