From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: from minnie.tuhs.org (minnie.tuhs.org [50.116.15.146]) by inbox.vuxu.org (Postfix) with ESMTP id 2259B2761C for ; Sat, 6 Jul 2024 14:52:58 +0200 (CEST) Received: from minnie.tuhs.org (localhost [IPv6:::1]) by minnie.tuhs.org (Postfix) with ESMTP id B668B43B1D; Sat, 6 Jul 2024 22:52:52 +1000 (AEST) Received: from pasta.tip.net.au (pasta.tip.net.au [203.10.76.2]) by minnie.tuhs.org (Postfix) with ESMTPS id 42C1F43ACB for ; Sat, 6 Jul 2024 22:52:42 +1000 (AEST) Received: from smtpclient.apple (203-7-124-164.dyn.iinet.net.au [203.7.124.164]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mailhost.tip.net.au (Postfix) with ESMTPSA id 4WGVfH3zZDz9R16; Sat, 6 Jul 2024 22:52:38 +1000 (AEST) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3774.600.62\)) From: sjenkin@canb.auug.org.au In-Reply-To: <20240705231714.5F0E58EE123E@ary.qy> Date: Sat, 6 Jul 2024 22:52:25 +1000 Content-Transfer-Encoding: quoted-printable Message-Id: <6DEE0364-13BF-4DDF-8B42-8EE9DE010211@canb.auug.org.au> References: <20240705213804.550128EDF53C@ary.qy> <20240705214901.GR26356@mcvoy.com> <20240705231714.5F0E58EE123E@ary.qy> To: TUHS X-Mailer: Apple Mail (2.3774.600.62) Message-ID-Hash: YKCLDCVQA24MHGHHF6TDUGCHTX5P337D X-Message-ID-Hash: YKCLDCVQA24MHGHHF6TDUGCHTX5P337D X-MailFrom: sjenkin@canb.auug.org.au X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-tuhs.tuhs.org-0; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: John Levine X-Mailman-Version: 3.3.6b1 Precedence: list Subject: [TUHS] Re: mental architecture models, Anyone ever heard of teaching a case study of Initial Unix? List-Id: The Unix Heritage Society mailing list Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: C wasn=E2=80=99t the first standardised coding language, FORTRAN & COBOL = at least were before it, so there were multi-platform source libraries and shared source, though = often single platform. =46rom what I know, vendor extensions of FORTAN, optimised for their = hardware, were common, making high-performance, portable source difficult or impossible. 6-bit = and 8-bit chars were the least of it. Is this right: C was the first =E2=80=99systems tool=E2=80=99 language + = libraries available across many platforms. Notionally, source code could be ported with zero or minimal = change. It made possible portable languages like PERL, PHP, Python. [ then came the "Tower of Babel" requiring tools like = =E2=80=98autoconf=E2=80=99 ] C became a bootstrapping environment for other portable languages & = tools, e.g. C++ & Golang. Secondly, portable systems tool languages with a common 2-part design of parser/front-end providing an abstract syntax tree=20 to multiple back-ends with platform specific code-generators. Are these back-ends where most of the assembler, memory model and = instruction optimisation take place now? > On 6 Jul 2024, at 09:17, John Levine wrote: >=20 > Back in the day getting a program to act the same on different > computers, was really hard, with the switch from IBM 7090 (36 bit word > addressed binary floating point) to IBM 360 (32 or 64 bit byte > addressed hex floating point) the most famous example. These days we > write code and compile it for x64 or ARM or RISC-V and for the most > part, it just works because the data formats and addressing are all > the same. -- Steve Jenkin, IT Systems and Design=20 0412 786 915 (+61 412 786 915) PO Box 38, Kippax ACT 2615, AUSTRALIA mailto:sjenkin@canb.auug.org.au http://members.tip.net.au/~sjenkin