Re: libefs

[Arturo Tena <arturo directmail org>]

Hello!

On Tue, 29 Jun 1999, Dietmar Maurer wrote:
> Hello,
> I'm working on libefs (file-system-inside-a-file) which can be used as
> storage driver for bonobo. I've just implemented a simple transaction
> handling (changes are only written after a commit) and wonder what I
> should do with old versions:
>     a) discard old versions and reuse the disk space as soon as
>     possible:
> or
>     b) never discard old versions and implement some kind of
>     version control (possibility to open old versions). I think this is
>     the Microsoft behavior (Use SaveAs to delete old versions).

I have some comments here:

No, MS doesn't have a version control in their files. libefs could be the
first in have that feature.

It would be great if the file-system-in-a-file could be mounted like any
other file system (with a little help of the kernel) but it must not be a
must. I mean, GNOME must be run in OSs where is impossible modify the
kernel to do that.

Back to the version control issue: it would be good, but libefs would had
to take care of other issues: multiuser modification, branches, merge the
changes, etc. The same kind of problems that CVS have to deal with.

Will libefs should deal with multiple applications trying to modify a file
inside the file? It can be implemented using a transaction monitor, but
that is a big project, isn't it?

Please, please, please, design libefs and the applications that will be
using libefs so if a file-system-in-a-file become damaged it would be
possible to open the file and read the not damaged part. I mean, when a
MSWord file is damaged, we can not read ANYTHING!! That is undesirable.
May be the file-system-in-a-file should be fault tolerant (!?).

May be libefs g[uys|als] could talk with the MSExcel plugin guy[s], in
order to not repeat the same stupid mistakes (like using a linked block
list, although libefs is using inodes right now).


--
Arturo Tena
arturo@directmail.org