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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Multi-channel rand()
Date: Wed, 26 Dec 2018 15:32:26 -0800
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Richard Damon <Richard@Damon-Family.org> writes:
[...]
> In many implementations, rand() IS based on the sample code from K&R,
> which is very old, very simple, and not very good. The fix isn't to add
> ad hoc randomizer fixes like you were suggesting, but to use a better
> random number generator, and a source of those algorithms was given earlier.
[...]

Some rand() implementations are even worse than the sample code
from K&R.  In the NetBSD implementation, the low order bit of the
value returned by rand() alternates 0 and 1, the low order 2 bits
repeat with a cycle of length 4. etc.  The K&R implementation
doesn't do that.

https://github.com/Keith-S-Thompson/crude_rand_test

-- 
Keith Thompson (The_Other_Keith) kst@mib.org  <http://www.ghoti.net/~kst>
Will write code for food.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"