[ILUG] hard- vs. soft-links [was: How to copy some files ]

[Brian Foster]

  | Date: Fri, 19 Jul 2002 22:00:02 +0100
  | From: "Matthew French" <mfrench42 at yahoo.co.uk>
  |[ ... ]
  | Now here is a thought: a Unix version of the "Deleted Items" folder.
  | 
  | In the root of a hard drive, create a directory ".unwanted".
  | Then periodically create hard links to every file on the hard
  | drive that does not have hard links.
  | 
  | That way, when someone accidentally does "rm *" or whatever,
  | you still have a link under ".unwanted"  [ ... ]

 hum.  interesting variation on the classic technique of
 redefining `rm' to `mv' the files into `./.trash/' (or
 with a prefix of `#' or a suffix of `~'; the variations
 are endless).  these classic techniques only provide a
 means to roll back accidental `rm's, so there is still
 considerable scope for data lost as there are other ways
 of deleting files --- which is not a problem for this
 hard link idea.

 but, like the classic techniques, there is no rolling
 back of accidental overwrites.

 ( rolling back overwrites reminds me of the "snapshot"
  facility on NetWork Appliance fileservers.  and of the
  various "versioning" filesystems which appeared --- and
  then vanished? --- over the years.... )

 one severe(?) gotcha is some files shouldn't have any
 hard links.  both RCS *,v (and hence CVS) and SCCS s.*
 files are like this --- the RCS(/CVS?)/SCCS toolsets
 complain if there are hard links.

cheers,
	-blf-
--
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