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From: crossd@gmail.com (Dan Cross)
Subject: [TUHS] Etymology of the open file table?
Date: Mon, 21 Mar 2016 23:02:45 -0400	[thread overview]
Message-ID: <CAEoi9W4XFq96F5tbahu9GGPY-1_Y1dsSirht1WmMJ0KNcW6FhA@mail.gmail.com> (raw)
In-Reply-To: <20160322022808.GA24345@mcvoy.com>

On Mon, Mar 21, 2016 at 10:28 PM, Larry McVoy <lm at mcvoy.com> wrote:

> 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.
>

Sure, but why does the second thing necessarily have to be a table? Does it?

        - Dan C.

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
>
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  parent reply	other threads:[~2016-03-22  3:02 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
2016-03-22  2:56     ` Warren Toomey
2016-03-22  3:02     ` Dan Cross [this message]
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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