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From: lm@mcvoy.com (Larry McVoy)
Subject: [TUHS] Etymology of the open file table?
Date: Mon, 21 Mar 2016 19:28:08 -0700	[thread overview]
Message-ID: <20160322022808.GA24345@mcvoy.com> (raw)
In-Reply-To: <CAOkr1zU5Ay8PaLsZeGNgnAei+cvbUXgp9Qyto78KrjvRyFC+NQ@mail.gmail.com>

So if you think about it you need two levels, the fd that is per open
that knows the offset, and the fd to the object in question.  The file
table is the latter.

On Mon, Mar 21, 2016 at 08:23:43PM -0600, Marc Rochkind wrote:
> A ref-counted data structure organized how, for what language? Integers are
> really easy to work with.
> 
> (Perhaps I misunderstood your post.)
> 
> On Mon, Mar 21, 2016 at 8:07 PM, Dan Cross <crossd at gmail.com> wrote:
> 
> > This came up today at work; what's the origin of the open file table? The
> > suggestion was made that, instead, a ref-counted data structure could be
> > allocated at open() time to serve the same purpose, and that a table of
> > open files was superfluous. My guess was that this made it (relatively)
> > easy to look up what files referred to a particular device?
> >

-- 
---
Larry McVoy            	     lm at mcvoy.com             http://www.mcvoy.com/lm 


  reply	other threads:[~2016-03-22  2:28 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-03-22  2:07 Dan Cross
2016-03-22  2:23 ` Marc Rochkind
2016-03-22  2:28   ` Larry McVoy [this message]
2016-03-22  2:56     ` Warren Toomey
2016-03-22  3:02     ` Dan Cross
2016-03-22  3:02   ` Dan Cross
2016-03-22  4:00     ` John Cowan
2016-03-22  4:11       ` Warner Losh
2016-03-23 19:48         ` Dan Cross
2016-03-23 20:17           ` John Cowan

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