Re: undelete?

david parsons (o.r.c@p.e.l.l.p.o.r.t.l.a.n.d.o.r.u.s)
26 Jul 1997 01:30:12 -0700


In article <linux.kernel.Pine.LNX.3.96.970724214136.11907A-100000@tittytwister.huwig.de>,
Kurt Huwig <kurt@huwig.de> wrote:
>Hello!
>In the FAQ, I just found "please wait".
>
>Is anyone working on an 'undelete'-feature for ext2 or better any
>filesystem? I don't need 'rm' replacements, because I want to undelete
>files deleted by samba.
>
>The easiest solution might by a fs on top of another fs that is fully
>transparent, but replaces 'delete' by a move into a certain directory.
>
>I heard that there was a thread about ext2 deletion. What about really
>deleting the stuff 60 seconds later? Often you realize your mistake just
>in the moment of pressing 'enter'.

That's not the way I'd do it; if you have a timed delete, you need to
keep timers running, and that seems like it might be a less than optimal
way to implement such a thing. I think the easiest way to implement
undelete would be to set up a scheme for doing whiteout on directory
entries; when you remove() (or unlink()?) a file, instead of killing
the directory entry it will simply white that entry out, for reaping by
a daemon at some later date (or recovery by undelete.) This way you
don't muck with the fs semantics of ext2, but simply implement a few
user-space daemons to do the proper bookkeeping on the filesystem.

____
david parsons \bi/ Plus you get to bypass the "difficulty is GOOD"
\/ cultists.