From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262278AbVAJOjx (ORCPT ); Mon, 10 Jan 2005 09:39:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262279AbVAJOjw (ORCPT ); Mon, 10 Jan 2005 09:39:52 -0500 Received: from smtpout.mac.com ([17.250.248.97]:25318 "EHLO smtpout.mac.com") by vger.kernel.org with ESMTP id S262278AbVAJOjl (ORCPT ); Mon, 10 Jan 2005 09:39:41 -0500 In-Reply-To: <41E27D29.2040001@grupopie.com> References: <20050107190536.GA14205@mtholyoke.edu> <20050107213943.GA6052@pclin040.win.tue.nl> <41E27D29.2040001@grupopie.com> Mime-Version: 1.0 (Apple Message framework v619) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: <747C0668-6315-11D9-B875-000D9352858E@mac.com> Content-Transfer-Encoding: 7bit Cc: Linux kernel , linux-os@analogic.com, "Patrick J. LoPresti" From: Felipe Alfaro Solana Subject: Re: /dev/random vs. /dev/urandom Date: Mon, 10 Jan 2005 15:39:38 +0100 To: Paulo Marques X-Mailer: Apple Mail (2.619) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 10 Jan 2005, at 14:03, Paulo Marques wrote: >> In the first place, the problem was to display the error of using >> an ANDing operation to truncate a random number. In the limit, >> one could AND with 0 and show that all randomness has been removed. > > Not really.. you just get a perfect random uniform distribution if the > range [0..0] :) I would say that a sample space (omega) of one unique element cannot be considered entirely random. For that if you perform the random experiment, you will always get that unique sample, and thus p(Sample) = p(Omega) = 1. Let Omega = { 0 }, thus p(Omega) = p(0) = 1, which I wouldn't consider random at all.