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    SubjectRe: Problem with random.c and PPC
    On Mon, Aug 19, 2002 at 05:11:03PM +0200, Marco Colombo wrote:
    > On Mon, 19 Aug 2002, Oliver Xymoron wrote:
    >
    > > > If you need a weak solution (a perturbated PRNG), just read a few bits
    > > > from /dev/random at times (but in a controlled and defined way).
    > >
    > > It might be helpful to think of /dev/urandom as akin to /dev/random with
    > > O_NONBLOCK. "Give me stronger bits if you got 'em" is desirable,
    > > otherwise this thread would be much shorter.
    >
    > "desirable", yes, I see... B-). But I have to understand why, yet.
    >
    > "Give me the best you can, but even 0 is ok" just serves to help people
    > waste resources. If your application is fine with (potentially)
    > guessable bits, you don't need /dev/random at all. If you do care
    > about a minimum, you know it in advance, so do fetch those bits
    > (and only them) from /dev/random, and use them. Yes, it may block,
    > but that's life. Resources aren't infinite.

    For most people, entropy input far exceeds entropy output and the pool
    is a finite size. There's no reason not to use these entropy bits as
    the pool is always full and we're discarding entropy constantly. It's
    only a problem when the pool is running low and we risk making
    /dev/random block.

    > I'm missing any real argument for having /dev/urandom logic into the
    > kernel.

    Convenience and control of resource sharing. The latter is slightly
    under-implemented.

    --
    "Love the dolphins," she advised him. "Write by W.A.S.T.E.."
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