From owner-freebsd-current Mon Oct 7 13:51:25 1996 Return-Path: owner-current Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id NAA27428 for current-outgoing; Mon, 7 Oct 1996 13:51:25 -0700 (PDT) Received: from phaeton.artisoft.com (phaeton.Artisoft.COM [198.17.250.211]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id NAA27413; Mon, 7 Oct 1996 13:51:17 -0700 (PDT) Received: (from terry@localhost) by phaeton.artisoft.com (8.6.11/8.6.9) id NAA14940; Mon, 7 Oct 1996 13:44:15 -0700 From: Terry Lambert Message-Id: <199610072044.NAA14940@phaeton.artisoft.com> Subject: Re: I plan to change random() for -current (was Re: rand() and random()) To: ache@nagual.ru (=?KOI8-R?Q?=E1=CE=C4=D2=C5=CA_=FE=C5=D2=CE=CF=D7?=) Date: Mon, 7 Oct 1996 13:44:14 -0700 (MST) Cc: terry@lambert.org, joerg_wunsch@uriah.heep.sax.de, freebsd-hackers@FreeBSD.org, current@FreeBSD.org, bde@zeta.org.au In-Reply-To: <199610071926.XAA04826@nagual.ru> from "=?KOI8-R?Q?=E1=CE=C4=D2=C5=CA_=FE=C5=D2=CE=CF=D7?=" at Oct 7, 96 11:26:04 pm X-Mailer: ELM [version 2.4 PL24] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-current@FreeBSD.org X-Loop: FreeBSD.org Precedence: bulk > > Unless you are a mathematical programmer, you are unlikely to be > > able to aprehend the consequences of even a trivial change away from > > mathematical standards will have. There are verifiable standards > > of correctness, and each standard dictates issues of precision to > > which one can trust the code. Obviously, differences after the > > significant digits can be ignored for comparison -- and are, in fact, > > stripped from results as the "noise" that they are. > > FYI, I am applied mathematic, B.S. degree. And I triple majored in high energy physics, applied mathematics, and computer science. This isn't a pissing contest. I would not be happy with *me* changing the interfaces for the same reasons I am not happy with *you* doing so. I can't trust me to be perfect any more than I can trust you to be perfect. > > I suggest strict adherence to standards -- mathematical standards, > > not ANSI or ISO C standards -- with regard to maintaining precision > > and historical implementation, as required to ensure repeatability > > and trust. > > Current random() code is joke from mathematical point of view (but not from > ANSI/ISO standards). It is why it needs fixing. All pseudo-random algoritms are cryptographically weak (as others have already pointed out). The only justification I've seen so far is the GIMP code, and it's a weak justification (you want me to carry around my own random generator, therefore I want the GIMP people to do the same). You haven't responded to the "heavily document and provide a compatability interface" compromise suggestion... how do you feel about that? It needs more work done to implement it, but it lets you achieve your goal without undue burden. See Jordan's last message... Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.