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

From: Brian Foster (blf at domain utvinternet.ie)
Date: Fri 19 Jul 2002 - 21:02:18 IST


  | Date: Fri, 19 Jul 2002 18:10:40 +0100
  | From: Ronan Waide <waider at domain waider.ie>
  |
  | On July 19, niall at domain linux.ie said:
  | > this case, [hard links] are being used to provide two quite
  | > different namespaces for the same set of files.
  |
  | Sure, but soft links would do the same. To be honest, I'm trying to
  | think of a useful use of hard links right now, and I'm a little
  | stumped. There's gotta be some benefit that I'm missing that's
  | immediately obvious to everyone.

 maybe, maybe not. yonks ago, I seem to recall dmr saying,
 or at least alleged to have said, something along the lines
 that soft and hard links both make sense in isolation, but
 having both does not. if this is even close to correct,
 yer in quite good company!

 there is at least one notable difference, and a host of minor
 ones. the notable difference is the data always exists (and
 is apriori accessible) for hard links --- there is no such
 thing as a broken link.

 I use this fact on occasion to "save" data, via the well-
 known attack of hard-linking to a supposedly-temporary file
 I want to preserve. the subsequent unlink(2)ing of the
 "temporary" file does not destroy the data.
 
cheers!
        -blf-

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