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=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: from minnie.tuhs.org (minnie.tuhs.org [IPv6:2600:3c01:e000:146::1]) by inbox.vuxu.org (Postfix) with ESMTP id D3DD522611 for ; Wed, 4 Dec 2024 20:04:22 +0100 (CET) Received: from minnie.tuhs.org (localhost [IPv6:::1]) by minnie.tuhs.org (Postfix) with ESMTP id 443E743CE2; Thu, 5 Dec 2024 05:04:20 +1000 (AEST) Received: from mail-qk1-x72c.google.com (mail-qk1-x72c.google.com [IPv6:2607:f8b0:4864:20::72c]) by minnie.tuhs.org (Postfix) with ESMTPS id B9FB043CE0 for ; Thu, 5 Dec 2024 05:04:14 +1000 (AEST) Received: by mail-qk1-x72c.google.com with SMTP id af79cd13be357-7b6648e25e3so5672285a.2 for ; Wed, 04 Dec 2024 11:04:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dartmouth.edu; s=google1; t=1733339054; x=1733943854; darn=tuhs.org; h=to:subject:message-id:date:from:mime-version:from:to:cc:subject :date:message-id:reply-to; bh=bZwuiNUWDn/l3HJ0AMAdhmUvAuH3+olnH8MpspzdYrQ=; b=d7X7kYp11LFzPLIZnloa/T31oRAuV8jt9mfjtJhvd88DTiNoMIY1NmF/mDfLXd/GgL ABMyYKCsVx1p2YuJkhtjynr3dsTf1+xDgsGjSk8U1ehghgQ6dhmgKu1+AaEVmc6gqSue 2abFAyQhcJVawG4+j3/eT4mQhGEn8FUp2Y5M6TjWdynYTvli0rYZnEhMhm4Pmyqwojp1 9vY/QH4ab9Ae2DvrRckjewOhNVbWqL1IaPMI3dk0XRqVZDYM38kKhfbLs0wSCcmWdu35 D5ENT4bNy3/f46qkSSf6tLzh4HAqS+MFbmIXsHOJ+1sI28xao3zwZXIa6trpDlDnYZYR XEvw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1733339054; x=1733943854; h=to:subject:message-id:date:from:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=bZwuiNUWDn/l3HJ0AMAdhmUvAuH3+olnH8MpspzdYrQ=; b=lUQjXepiZcFckZyJ12hGA5ZiYCoJrKnf3jCW6mBHcr3daD1MVmP+sWb31wq3FkP4f3 Y+znw9xfAziIyepzqXhjG5RAqjgSojeP0UxsrAFehOw5EqEU0bbRRPfvhYUWXE2Wb67N waqGvlGbenWGaNMyIIapdlrOw1C7djHOF0FpdPD5eC4rOmAiw6TO3KoWcltAxzxzwr40 vKeDvkwkZsOSNDamwUZFcJFI/G5fAP77NIypoH6jZFvC2JPWSUoM7nCoba9ujmHAcrFw 26FyM74WM0iU/5RyoBdolrg5pmS8g2PHUpSqg9VmvkRxRHsL7sys6tpO1V6emgxeD/Ls Brvg== X-Gm-Message-State: AOJu0Yw5vJAhWNKFAtNuXo6GUnYfyEOZKI5fjQX3RjXe/RMlgEArWRqQ RXvUhq8tAc0bPiG8ogJS8Sn/1X0ZRImze3b4Z1QFN/ViWXRc+6pK1ExY/FelXxV5h0emSSI3J0W /rk1YHzRDOJ0uJZVjOSN1M/jN8gnNqh8P7q6zc+94Y2eu9CYh X-Gm-Gg: ASbGncvxoToOzfQvQQnfATgHNVnnpcEHIcI7oTRUfiDGWGVDCkC3ZcYMsw/IjHgGJdj 1H49OoQXFK/oVtcn2Vg5tJBDe/BgKuVg= X-Google-Smtp-Source: AGHT+IH+0BRVEDVGTFWV3DvCjBSTS9RG0bLJxH8+8LXZOAKGLmJHp2A6zC3NLB+p6ITtLqO5ecKR8b7JJ/aC1gnwKO4= X-Received: by 2002:a05:620a:24c4:b0:7ae:d2d0:190d with SMTP id af79cd13be357-7b6a5da0f58mr814386685a.32.1733339053841; Wed, 04 Dec 2024 11:04:13 -0800 (PST) MIME-Version: 1.0 From: Douglas McIlroy Date: Wed, 4 Dec 2024 14:03:58 -0500 Message-ID: To: COFF Content-Type: text/plain; charset="UTF-8" Message-ID-Hash: H4W6HOENR7LC6RZKD64WHMXEMOST7ZIS X-Message-ID-Hash: H4W6HOENR7LC6RZKD64WHMXEMOST7ZIS X-MailFrom: douglas.mcilroy@dartmouth.edu X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.6b1 Precedence: list Subject: [COFF] Re: [TUHS] After 50 years, what has the Impact of Unix been? List-Id: Computer Old Farts Forum Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Apropos of file types, which Rich Salz commends Unix for discarding. Early in Multics development, I and others visited various influential time-sharing systems in search of good ideas. I tried each one on a simple model of software updating, in particular of remaking a compiler. In every instance I could not make my program work without expert help to get past file-type barriers. My model was based on a trivial Fortran program that copied input to output until an input line with END in column 7 had been processed. Every system was able to compile this program, but ... After compiling, I tried to use the program to make a copy of itself. Here was the first file-type hurdle. Input was typically expected to be of type data, not source code. Gurus had to scramble to overcome this nominal incompatibility. Next I tried to compile the new Fortran program. Same trouble in reverse--data used as source. More scrambling of gurus. Then I ran the newly compiled program to do the above steps over again. This time the gurus had the file-type workarounds under control. One comp center still had trouble, however, which took some time to diagnose. It turned out that Fortran programs were, for unknown reasons, specifically forbidden to read their own source code! One side effect of file-type conventions was that instead of learning once and for all how to create text files, one had to learn different ways to edit files of different types. Doug