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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: How do I write directly to a memory address?
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Date: Fri, 4 Feb 2011 18:40:48 +0100
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Date: 2011-02-04T18:40:48+01:00
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On Fri, 04 Feb 2011 11:00:18 -0500, Hyman Rosen wrote:

> Did I mention that people who criticize C are like people
> who criticize grammar? Every time they do so, their own
> criticism contains errors.

Right, because nobody really understands C, there is no way to reason about
C without running into errors.

> You make two errors here. The first is to assume without
> any actual knowledge that it is possible for the argument
> to be a null pointer; it is likely that the contract for
> this procedure requires that it not be. The second is that
> you test for the pointer being null each time through the
> loop rather than just once.

You just made the error of which you accused Ludovic. You assumed a
contract that the pointer cannot be modified within the loop, e.g. upon
video buffer modification.

Quality of a programming language is in great part about how close
different people could understand explicit and implied contracts when
reading the code.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de