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Date:      Tue, 23 Sep 2008 22:40:57 +0100
From:      RW <fbsd06@mlists.homeunix.com>
To:        freebsd-questions@freebsd.org
Subject:   Re: using /dev/random
Message-ID:  <20080923224057.46955938@gumby.homeunix.com.>
References:  <18648.30321.369520.631459@jerusalem.litteratus.org>

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On Tue, 23 Sep 2008 11:52:07 -0400
Lowell Gilbert <freebsd-questions-local@be-well.ilk.org> wrote:

> Robert Huff <roberthuff@rcn.com> writes:
> 
> > 	What is the canonical way to get data from /dev/random?
> > Specifically: having opened the file, how do I read the stream?
> > I'm currently using
> >
> >
> >   union {
> >     float f;
> >     char c[4];
> >   } foo;
> >
> >   foo.f = 0.0;
> >
> >   fscanf(rand_fp,"%4c",foo.c);
> >
> >
> > 	which doesn't seem to produce anywhere near "random bytes"
> > as promised by the man page.
> 
> Have you turned off the "seeded" variable?  You'll fall back to a
> software pseudorandom sequence if you don't.

kern.random.sys.seeded is just a flag that gets set to 1 on each
reseed. IIRC it's also initialized to 1 so it doesn't actually do
anything very useful.






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