> the man page for "rm" talks about the "-W" flag, which is supposed to
> recover files covered by whiteouts. what are they? it also references
> "undelete(2)", for which there does not appear to be a man page.
> is this a real method of undeleting files? if so, is there a way to
> make sure a file cannot be undeleted?

I noticed a reference to `whiteout' file types when I was poking
through the filesystem source code the other day. I didn't look
too closely, but I get the impression that it's intended to be part
of a way to `delete' a file without really deleting it, though
creating opaque `whiteout' directories that the files get moved
to.

If you want to remove a file permanently, use the -P option on rm:

     -P    Overwrite regular files before deleting them.  Files are overwrit-
           ten three times, first with the byte pattern 0xff, then 0x00, and
           then 0xff again, before they are deleted.

cjs

Curt Sampson    curt@portal.ca		Info at http://www.portal.ca/
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