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From: "Douglas A. Gwyn" <DAGwyn@null.net>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] how to avoid a memset() optimization
Date: Wed, 20 Nov 2002 16:38:36 +0000	[thread overview]
Message-ID: <3DDBB1FF.9DF78E7C@null.net> (raw)
In-Reply-To: <Pine.GSO.4.44.0211200817190.5837-100000@peppar.cs.umu.se>

Tomas wrote:
> I've been fantasizing about having some sort of atreturn()
> functionality similar to atexit() to use in error handling (as
> soon as a file is opened, do an atreturn() and specify that that
> fd should be closed upon a "return -1;" but not otherwise, for
> example).
> Has anyone else been thinking in that direction? Does anyone have
> references to mailing list/usenet discussions or papers about
> such a feature?

Back in the Good Old Days (tm), we had what we called "completion
routines".  In an I/O service call one could optionally include a
pointer to a completion routine, which the OS would invoke after
the operation was complete.  (Of course the service call returned
immediately without waiting for the operation to complete.)

In C you could invent an API implemented as macros that would do
more or less what you indicated; there would have to be a label
near the end of the function.  It's not obvious that this buys
you very much, unlike general exception handling which spans
multiple function depth.


  reply	other threads:[~2002-11-20 16:38 UTC|newest]

Thread overview: 91+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-11-19 14:32 presotto
2002-11-20  7:24 ` Tomas
2002-11-20 16:38   ` Douglas A. Gwyn [this message]
  -- strict thread matches above, loose matches on Subject: below --
2003-01-06 10:47 nigel
2003-01-06 11:15 ` Geoff Collyer
2002-11-19  8:21 Fco.J.Ballesteros
2002-11-18 21:36 Joel Salomon
2002-11-18 20:42 Andrew Simmons
2002-11-18 14:19 C H Forsyth
2002-11-15  1:56 Dennis Ritchie
2002-11-15 10:51 ` Douglas A. Gwyn
2002-11-15 12:03 ` Boyd Roberts
2002-11-14 18:55 jmk
2002-11-14 22:23 ` Steve Kilbane
2002-11-14 18:17 presotto
2002-11-14 18:11 Joel Salomon
2002-11-14 18:26 ` William Josephson
2002-11-14 17:44 rog
2002-11-15 10:50 ` Douglas A. Gwyn
2002-11-14 17:28 Russ Cox
2002-11-14 16:47 presotto
2002-11-15 10:50 ` Douglas A. Gwyn
2002-11-15 16:51   ` William Josephson
2002-11-18 10:38     ` Douglas A. Gwyn
2002-11-18 12:34       ` Ronald G. Minnich
2002-11-19  7:38 ` Roman V. Shaposhnick
2002-11-20  9:47   ` Douglas A. Gwyn
2002-11-21 20:55     ` Roman V. Shaposhnick
2002-11-22  9:59       ` Douglas A. Gwyn
2003-01-06 10:18   ` Ralph Corderoy
2003-01-06 15:42     ` Sam
2003-01-06 15:49       ` Russ Cox
2003-01-06 15:58         ` David Presotto
2003-01-06 16:02         ` Sam
     [not found] <nemo@plan9.escet.urjc.es>
2002-11-14 15:38 ` Fco.J.Ballesteros
2002-11-14 16:24   ` Scott Schwartz
2002-11-14  6:53 Russ Cox
2002-11-14 10:22 ` Douglas A. Gwyn
2002-11-14 13:20   ` Sam
2002-11-14 15:20     ` Scott Schwartz
2002-11-14 15:26       ` Boyd Roberts
2002-11-14 15:34         ` plan9
2002-11-14 15:59           ` Sam
2002-11-14 18:57         ` Steve Kilbane
2002-11-15 10:51           ` Douglas A. Gwyn
2002-11-14 15:50       ` Dan Cross
2002-11-14 17:21         ` Douglas A. Gwyn
2002-11-14 18:51           ` Dan Cross
2002-11-14 15:50     ` Douglas A. Gwyn
2002-11-19  7:20 ` Roman V. Shaposhnick
2002-11-14  2:48 Dennis Ritchie
2002-11-14  4:23 ` Ronald G. Minnich
2002-11-13 18:58 Rob `Commander' Pike
2002-11-13 14:40 C H Forsyth
2002-11-13 15:54 ` rob pike
2002-11-13 16:05   ` andrey mirtchovski
2002-11-13 16:32   ` Ronald G. Minnich
2002-11-14 10:21     ` Douglas A. Gwyn
2002-11-14 17:07       ` Ronald G. Minnich
2002-11-22  9:59     ` Clint Olsen
2002-11-13 16:56   ` William K. Josephson
2002-11-14 10:21     ` Douglas A. Gwyn
2002-11-14 16:48       ` William Josephson
2002-11-14 10:21   ` Douglas A. Gwyn
2002-11-14 14:46     ` Dan Cross
2002-11-14 16:59       ` Douglas A. Gwyn
2002-11-14 18:31         ` Tad Hunt
2002-11-15 10:50           ` Douglas A. Gwyn
2002-11-18 14:27         ` Aharon Robbins
2002-11-13 14:14 Skip Tavakkolian
2002-11-13 13:55 rog
2002-11-13 13:38 Skip Tavakkolian
2002-11-13 16:25 ` Boyd Roberts
2002-11-13 10:43 C H Forsyth
2002-11-14 10:21 ` Douglas A. Gwyn
2002-11-13  6:52 Geoff Collyer
2002-11-13 10:13 ` Boyd Roberts
2002-11-13  6:34 Andrew Simmons
2002-11-13  6:43 ` Doc Shipley
2002-11-13  1:47 Russ Cox
2002-11-13 10:16 ` Douglas A. Gwyn
2002-11-14  1:46 ` Roman V. Shaposhnick
2002-11-14  1:52   ` William Josephson
2002-11-14  6:42     ` Roman V. Shaposhnick
2002-11-13  0:31 Russ Cox
2002-11-13  1:26 ` Roman V. Shaposhnick
2002-11-13 10:15   ` Douglas A. Gwyn
2002-11-14  1:42     ` Roman V. Shaposhnick
2002-11-13 10:15 ` Douglas A. Gwyn
2002-11-13  0:20 presotto
2002-11-12 22:42 Roman V. Shaposhnick

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