From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 23506 invoked from network); 21 Dec 2021 21:43:03 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 21 Dec 2021 21:43:03 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id E95039CEC3; Wed, 22 Dec 2021 07:42:55 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id E3CA79CE85; Wed, 22 Dec 2021 07:42:23 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id D85F79CE75; Wed, 22 Dec 2021 07:42:21 +1000 (AEST) Received: from mercury.lcs.mit.edu (mercury.lcs.mit.edu [18.26.0.122]) by minnie.tuhs.org (Postfix) with ESMTPS id 5C1E39CC2E for ; Wed, 22 Dec 2021 07:42:21 +1000 (AEST) Received: by mercury.lcs.mit.edu (Postfix, from userid 11178) id 4A13118C07A; Tue, 21 Dec 2021 16:42:20 -0500 (EST) To: tuhs@minnie.tuhs.org Message-Id: <20211221214220.4A13118C07A@mercury.lcs.mit.edu> Date: Tue, 21 Dec 2021 16:42:20 -0500 (EST) From: jnc@mercury.lcs.mit.edu (Noel Chiappa) Subject: Re: [TUHS] PDP 11/23 running UNIX version 6 at VCF Midwest! X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: jnc@mercury.lcs.mit.edu Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" > From: Paul Ruizendaal > Does anyone remember, was this a real life bug back in 6th edition The 'V6' at MIT (actually, PWB1) never had an issue, but then again, its TTY driver (here: http://ana-3.lcs.mit.edu/~jnc/tech/unix/mit/dmr/tty.c if anyone wants to see it) was heavily re-written. But from the below, it's almost certainlynothing to do with the TTY code... > From: Dave Plonka > one experiment we did was to redirection the bas(1)ic program's output > to a file and what we found was that (a) characters would still > sometimes be lost Good test. If you all want to chase this down (I can lend V6 expertise, if needed), I'd say the first step is to work out whether it's the application, or the system, losing the characters. To do that, I'd put a little bit of code in write() to store a copy of data sent through that in a circular buffer, along with tagging it with the writing process, etc. Once you figure out where it's getting lost, then you can move on to how/why. > From: Clem Cole > First Sixth Edition does not have support for either the 11/23 Yeah, but it's super-trivial to add /23 support to V6: http://gunkies.org/wiki/Running_UNIX_V6_on_an_-11/23 The only places where change is needed (no LKS register, no switch register, and support for more than 256KB of main memory - and that one one can get by without), it's hard to see how they could cause this problem. > One other thought, I'm pretty sure that Noel's V6+ system from MIT can > support a 23 No, we never ran than on a /23 BITD (no need, no mass storage); and I have yet to bring the V6+ system up (although I have all the bits, and intend to, at some point, to get its TCP/IP running). I've been using stock (well, hacked a bit, in a number of ways - e.g. 8-bit serial line output) V6. Noel