Re: Fair, truly random random number generator

From	raltbos@xs4all.nl (Richard Bos)
Newsgroups	comp.lang.c
Subject	Re: Fair, truly random random number generator
Date	2016-11-04 17:59 +0000
Organization	Go wash your mouth.
Message-ID	<581ccbda.4974046@news.xs4all.nl> (permalink)
References	(2 earlier) <nv0sno$279$1@dont-email.me> <nvbcu4$fjm$1@dont-email.me> <01bf1ea3-23bf-4c46-8d1e-506ad6dbfa81@googlegroups.com> <nvgmb9$63r$1@dont-email.me> <lnlgx0xcvx.fsf@kst-u.example.com>

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Keith Thompson <kst-u@mib.org> wrote:

> "Chris M. Thomasson" <invalid@invalid.invalid> writes:
> [...]
> > This is why I think race-conditions in multi-threaded programs can be 
> > considered random in the sense that its damn near impossible to hit a 
> > defined period of repetition.
> 
> That's not all that "random" means.  It might be very difficult to
> predict the next -- well, whatever numeric value you might derive from a
> race condition.  But if it's possible to make *some* prediction at rates
> better than chance, it's not random.

That would mean that a stochastic, but bell-shaped distribution isn't
random. I don't think you're entirely wrong, but you're not entirely
right, either.

As for multi-threaded timings, they're not random because 
a) a sufficiently deep program could in theory predict them, and 
b) a sufficiently devious program could in theory manipulate them.

And all C programs are, of course, in a state of sin.

Richard

Thread

Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-28 20:31 +0800
  Re: Fair, truly random random number generator "Osmium" <r124c4u102@comcast.net> - 2016-10-28 07:48 -0500
    Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-28 21:07 +0800
      Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-28 14:21 +0100
        Re: Fair, truly random random number generator Gareth Owen <gwowen@gmail.com> - 2016-10-28 16:22 +0100
          Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-28 16:30 +0100
            Re: Fair, truly random random number generator Gareth Owen <gwowen@gmail.com> - 2016-10-28 16:32 +0100
        Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-29 23:11 +0800
          Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-31 11:17 +0000
            Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-31 20:14 +0800
              Re: Fair, truly random random number generator Melzzzzz <Melzzzzz@zzzzz.com> - 2016-10-31 12:32 +0000
                Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-31 12:48 +0000
                Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-01 15:30 +0800
              Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-31 12:47 +0000
      Re: Fair, truly random random number generator "Osmium" <r124c4u102@comcast.net> - 2016-10-28 09:32 -0500
  Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-10-28 07:14 -0700
    Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-10-28 18:07 -0700
      Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-01 17:45 -0700
        Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-01 18:57 -0700
          Re: Fair, truly random random number generator David Brown <david.brown@hesbynett.no> - 2016-11-02 10:06 +0100
            Re: Fair, truly random random number generator "Osmium" <r124c4u102@comcast.net> - 2016-11-02 04:46 -0600
            Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-02 05:06 -0700
              Re: Fair, truly random random number generator David Brown <david.brown@hesbynett.no> - 2016-11-02 13:43 +0100
                Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-02 06:02 -0700
                Re: Fair, truly random random number generator David Brown <david.brown@hesbynett.no> - 2016-11-02 16:08 +0100
                Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-02 08:21 -0700
              Re: Fair, truly random random number generator Mark Storkamp <mstorkamp@yahoo.com> - 2016-11-02 08:20 -0500
          Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-03 17:56 -0700
            Re: Fair, truly random random number generator Keith Thompson <kst-u@mib.org> - 2016-11-03 18:16 -0700
              Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-03 18:48 -0700
              Re: Fair, truly random random number generator supercat@casperkitty.com - 2016-11-04 09:17 -0700
              Re: Fair, truly random random number generator raltbos@xs4all.nl (Richard Bos) - 2016-11-04 17:59 +0000
                Re: Fair, truly random random number generator Keith Thompson <kst-u@mib.org> - 2016-11-04 11:55 -0700
                Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-04 12:43 -0700
                Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-04 12:40 -0700
            Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-04 12:49 -0700
              Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-04 13:23 -0700
                Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-04 13:32 -0700
                Re: Fair, truly random random number generator ImperiusDamian <damianblack.wolf@gmail.com> - 2016-11-05 18:48 -0400
                Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-05 16:03 -0700
                Re: Fair, truly random random number generator "Chris M. Thomasson" <invalid@invalid.invalid> - 2016-11-05 16:50 -0700
                Re: Fair, truly random random number generator ImperiusDamian <damianblack.wolf@gmail.com> - 2016-11-05 19:52 -0400
                Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-05 17:06 -0700
    Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-29 23:13 +0800
      Re: Fair, truly random random number generator Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2016-10-29 12:12 -0400
        Re: Fair, truly random random number generator "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-30 00:22 +0800
        Re: Fair, truly random random number generator Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2016-10-29 12:26 -0400
        Re: Fair, truly random random number generator supercat@casperkitty.com - 2016-10-29 09:44 -0700
          Re: Fair, truly random random number generator Tim Rentsch <txr@alumni.caltech.edu> - 2016-11-01 08:13 -0700
            Re: Fair, truly random random number generator supercat@casperkitty.com - 2016-11-01 08:31 -0700
              Re: Fair, truly random random number generator Tim Rentsch <txr@alumni.caltech.edu> - 2016-11-02 12:58 -0700
      Re: Fair, truly random random number generator "James R. Kuyper" <jameskuyper@verizon.net> - 2016-10-29 12:37 -0400
      Re: Fair, truly random random number generator Keith Thompson <kst-u@mib.org> - 2016-10-29 11:57 -0700
      Re: Fair, truly random random number generator David Brown <david.brown@hesbynett.no> - 2016-10-30 17:13 +0100
        Re: Fair, truly random random number generator "Osmium" <r124c4u102@comcast.net> - 2016-10-30 11:07 -0600
          Re: Fair, truly random random number generator supercat@casperkitty.com - 2016-10-30 12:20 -0700
      Re: Fair, truly random random number generator Richard Heathfield <rjh@cpax.org.uk> - 2016-10-31 11:18 +0000
      Re: Fair, truly random random number generator Ed Prochak <edprochak@gmail.com> - 2016-11-03 10:39 -0700
        Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-03 11:13 -0700
          [OT] gigawatts = gigaseconds correlation? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-04 02:36 +0800
            Re: [OT] gigawatts = gigaseconds correlation? "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-03 12:07 -0700
              Re: [OT] gigawatts = gigaseconds correlation? "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-04 12:02 +0800
          Re: Fair, truly random random number generator gazelle@shell.xmission.com (Kenny McCormack) - 2016-11-03 19:56 +0000
          Re: Fair, truly random random number generator "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-03 16:21 -0700
  Re: Fair, truly random random number generator luser droog <luser.droog@gmail.com> - 2016-10-29 14:49 -0700
    Re: Fair, truly random random number generator jameskuyper@verizon.net - 2016-10-29 15:29 -0700
  Re: Fair, truly random random number generator Quadibloc <jsavard@ecn.ab.ca> - 2016-10-29 19:09 -0700
  Thank you all for the replies! "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-10-31 18:42 +0800

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