[Scottish] allowing a large newborn sea-mammal to collide with a rocky plane toid object devoid of atmosphere somewhere in another galaxy

John Hallam scottish at mailman.lug.org.uk
Fri Mar 21 09:07:06 2003

On Thu, 20 Mar 2003, Huard, Elise - D C&W Consultant wrote:

> Or to phrase it differently : i need a random number generator that won't
> give the same sequence of numbers every time that the seed is reinitialised
> in the same second (by 2 different users)
> srand(time(NULL))
> and then rand()
> doesn't work.
> Or a different kind of seed ?  Suggestions are welcome (should be readily
> available in your standard Unix system)

	One thing you can do is to execute `ps' and hash the output, e.g.
with MD5, and use some of those bits as your seed.  There is enough going
on in a PS output to make duplicate seeds rather unlikely, unless
(perhaps) you have a multiple CPU machine which can execute multiple ps
invocations simultaneously...

	As someone else said, be careful with rand() if you want good
random sequences -- some rand()s are seriously broken.  A good cheap
random number generator is the Mersenne Twister, which you can find at