From: ralph@inputplus.co.uk (Ralph Corderoy)
Subject: [TUHS] rm command
Date: Wed, 25 Apr 2018 23:09:16 +0100 [thread overview]
Message-ID: <20180425220916.63C52206BE@orac.inputplus.co.uk> (raw)
In-Reply-To: <C15B0B7C-EC7E-44E3-ACF2-E8461C2C49E8@jctaylor.com>
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Hi Bill,
> I think it’s a bit more interesting to uncover why rm does not remove
> directories by default thereby obviating the need for rmdir
Well, I'd guess it's: rm just does a single unlink to decrement an
inode's reference count by one, actually increment it since they were
negative, whereas rmdir on an empty directory needs to do two
decrements, one for its directory entry in the parent, and one for `..'.
(I think hard links could apply to directories in the early days, until
it made things too awkward, e.g. du(1) and cycles.)
--
Cheers, Ralph.
https://plus.google.com/+RalphCorderoy
next prev parent reply other threads:[~2018-04-25 22:09 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-04-25 20:22 Eric Blood
2018-04-25 21:23 ` Ralph Corderoy
2018-04-25 21:33 ` John P. Linderman
2018-04-25 21:53 ` William Corcoran
2018-04-25 21:58 ` Derek Fawcus
2018-04-25 22:09 ` Ralph Corderoy [this message]
2018-04-25 22:17 Noel Chiappa
2018-04-27 16:26 ` Dave Horsfall
2018-04-27 16:58 ` Ian Zimmerman
2018-04-27 18:14 ` Steve Nickolas
2018-04-27 18:17 ` Pete Wright
2018-04-28 16:33 ` Michael Kjörling
2018-04-28 18:01 ` Ian Zimmerman
2018-04-28 18:51 ` Derek Fawcus
2018-04-26 2:19 Doug McIlroy
2018-04-26 9:41 ` Ralph Corderoy
2018-04-27 16:42 Noel Chiappa
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