From:	"John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Srandom
Date:	Mon, 30 Mar 1998 21:52:15 -0500
Organization:	Two pounds of chaos and a pinch of salt.
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Message-ID:	<35205A5F.6C23@cs.com>
References:	<19980330 DOT 202928 DOT 14806 DOT 0 DOT matthew DOT krause AT juno DOT com>
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To:	djgpp AT delorie DOT com
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Matthew R Krause wrote:
> 
> Wouldn't using the previous random number as a seed work better? In other
> words, start with the time as a seed and generate a random number 'x'.
> Seed random with 'x' next time, and set 'x' as new seed?
> I'm not sure about this, though, and __please__ tell if I'm wrong!!

Well, sort of.  However, random(), as opposed to rand(), uses a highly
complex mathematical algorithm for generating random values, and
reseeding it each time it runs, especially if the seed is based on a
prior value of the algorithm, could theoretically produce
non-randomness.  As a practical matter, nobody has ever tested it.

Besides, the problem is that if a program fork()s itself, the child
process will inherit the parent's seed, and therefore an identical
series of random numbers.  There has to be some way to make it use a
different seed in each process.

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