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, RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 31633 invoked from network); 10 Jun 2021 07:59:39 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 10 Jun 2021 07:59:39 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id 6551F93FAD; Thu, 10 Jun 2021 17:59:36 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id CA79F93D1B; Thu, 10 Jun 2021 17:58:47 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id 9DDA893D1B; Thu, 10 Jun 2021 17:58:44 +1000 (AEST) Received: from freefriends.org (freefriends.org [96.88.95.60]) by minnie.tuhs.org (Postfix) with ESMTPS id 973B193D06 for ; Thu, 10 Jun 2021 17:58:43 +1000 (AEST) X-Envelope-From: arnold@skeeve.com Received: from freefriends.org (freefriends.org [96.88.95.60]) by freefriends.org (8.14.7/8.14.7) with ESMTP id 15A7wepU013328 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 10 Jun 2021 01:58:41 -0600 Received: (from arnold@localhost) by freefriends.org (8.14.7/8.14.7/Submit) id 15A7weqm013326; Thu, 10 Jun 2021 01:58:40 -0600 From: arnold@skeeve.com Message-Id: <202106100758.15A7weqm013326@freefriends.org> X-Authentication-Warning: frenzy.freefriends.org: arnold set sender to arnold@skeeve.com using -f Date: Thu, 10 Jun 2021 01:58:40 -0600 To: tuhs@minnie.tuhs.org, imp@bsdimp.com References: In-Reply-To: User-Agent: Heirloom mailx 12.5 7/5/10 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Subject: Re: [TUHS] System IV 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: , Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" Warner Losh wrote: > So I've seen a number of places that talk about Unix TS 3.0 -> 4.0 -> 5.0 > progression and how System III was released and System V was released and > System IV was internal only. > > What I've not seen is the "why" part of this. Why was it internal only? > > Warner I did some contract programming at Southern Bell (one of the operating companies) for a while, starting in the summer of 1982. We used USG Unix 4.0 on a PDP-11/70. There were also vaxen. It was no longer being called PWB by then. In fact, I think that PWB was V6 based and an ancestor of System III. System III had been released to the world. When I asked why AT&T hadn't released Unix 4.0, I was told that the policy was to release one version behind what was being run internally. After the Bell System break up (1/1/1984), AT&T decided to just release what was current, thus the jump to System V, with "System IV" never having gotten outside the Bell System. When I was doing the contract work, although we were on Unix 4.0, we used documentation from Unix 3.0; they didn't bother reprinting / updating the manuals since the primary changes were apparently performance improvements in the kernel. (For example, they moved to hash tables for many things instead of simple linked lists.) I still have the reference manual and the photocopies I made of all the other documentation. :-) There was also a screen editor, named 'se' (NOT related to the Georgia Tech 'se' editor) which they'd managed to shoehorn onto the '11. It was kinda cool. I used both it and 'ed'. vi was also available but I found the modal stuff weird and didn't end up learning it until a year or two later. :-) Hope this is of interest. Arnold