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From: new@ee.udel.edu (Darren New)
Newsgroups: comp.lang.misc
Subject: Re: Array references cannot be made optimal
Message-ID: <36561@nigel.ee.udel.edu>
Date: 16 Nov 90 15:43:12 GMT
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In article <27546@megaron.cs.arizona.edu> gudeman@cs.arizona.edu (David Gudeman) writes:
>In article  <6045:Nov1519:34:2290@kramden.acf.nyu.edu> Dan Bernstein writes:
>]Well, I can't remember ever debugging a non-terminating program that
>]*didn't* have a rather simple infinite loop, and I remember debugging
>]lots of programs where the loop was simple. Does your experience differ?
>
>The word "simple" here is ambiguous.  If you mean that the loop was
>fairly small, I guess most of them are.  If you mean that the number
>of states traversed in a cycle is small, then yes, my experience
>differs.  It seems to me that there is almost always at least some
>monotonic action going on in a loop (which is the reason for having
>the loop), and this action will create very long state cycles.
>
>]I'd be interested in seeing your example.
>

Here is a really simple example that has stung me a couple of times. Once,
this ran for two days before I noticed it had never finished.

$ cat xyz* >xyzzy

This will eventually fill up the entire disk, never once entering the same
state.                  -- Darren
-- 
--- Darren New --- Grad Student --- CIS --- Univ. of Delaware ---
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