Re: [Zcip] embeddable zeroconf/ip code

David Brownell wrote:
> On Monday 18 October 2004 12:21 pm, H. Peter Anvin wrote:
> 
> 
>>Please use srand48() and lrand48() or mrand48() instead of srandom() 
>>and  random().  The former set of functions are well-defined across 
>>implementations, whereas the latter can be arbitrarily complex and
>>therefore  behave differently.  For this application, I believe it is better
>>if everyone uses the *same* PRNG.
> 
> 
> That was from the original, FWIW; easy to change.
> 
> I don't think "same" PRNG matters anywhere near as much as having
> any single machine have a repeatable/reproducible first guess.  Why
> should it matter if different PRNGs are used to guess?  Though it would
> be nice to be able to use all 48 bits of etheraddr in the seed ... ;)
> 

Yes, seed48() is the right function, not srand48() as I mistakenly said.

It does matter for the PRNGs because of the "P" part -- we're not using them 
as RNGs but as a hash sequence generator indexed based on the MAC.

	-hpa


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