Subject: Re: replace kernel random number function
To: Robert Elz <kre@munnari.OZ.AU>
From: Mike Pelley <>
List: tech-kern
Date: 10/24/2000 11:06:12
> > sys/arch/sparc/sparc/clock.c assumes that random(9) returns uniform
> > random number (at least the comment says so).
> Unless I am horribly confused, isn't "uniform" a necessary property
> of anything that is truly a random number?   That is, if the number
> selection is biased, it isn't truly random is it?   Is there something
> about the kernel's random number generation (the good one) which makes
> it not generate uniform numbers ?

The original should probably have said a uniform pseudo-random number.  A
series of truly random numbers (if such a thing exists ;o) is not  bound by
any constraints, including uniformity.  This series can represent any
possible sequence, including those that look "biased".  Even over a long
series there is often noticeable clumping of numbers close together, which
can be inconvenient if a uniform distribution was the goal.