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=DKIM_SIGNED,DKIM_VALID, HTML_MESSAGE,MAILING_LIST_MULTI,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 1618 invoked from network); 10 Apr 2022 20:44:30 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 10 Apr 2022 20:44:30 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id ED1249BCDE; Mon, 11 Apr 2022 06:44:27 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 040149B72B; Mon, 11 Apr 2022 06:43:55 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=pass (2048-bit key; unprotected) header.d=ccil-org.20210112.gappssmtp.com header.i=@ccil-org.20210112.gappssmtp.com header.b="tLKonjDy"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 4CFF79B72B; Mon, 11 Apr 2022 06:41:50 +1000 (AEST) Received: from mail-pl1-f175.google.com (mail-pl1-f175.google.com [209.85.214.175]) by minnie.tuhs.org (Postfix) with ESMTPS id 8211F9B6CA for ; Mon, 11 Apr 2022 06:41:49 +1000 (AEST) Received: by mail-pl1-f175.google.com with SMTP id s14so2626909plk.8 for ; Sun, 10 Apr 2022 13:41:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ccil-org.20210112.gappssmtp.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=i8Z9JW71iuJMVJKowo55YUhlmbC60cA0lzzprLCJ5rA=; b=tLKonjDyb0hvQwFV6ELMT6nRn3cNXW49zBxygy3K2iRi7RXhhYepFam/RPiThf1ubL FBeDjm/RVPSEYRhQ8pt3WdUksyJi/6T3hpWWpFXJfyIDtsU2A10daBDJGDbW9PYa1rK0 94OFO4u3mxMR+yO7HXIMz/JR1n3moRYpSC5V0IUZTwJAYxI7Ex6uOA8FresVHfVZDMSP 6VVVRwTkfgXbVTo5LbOlycpAvyin3lO0Fk7lxUB9lWtiTxZC6DONE7QV6YNAR21fd2SK hRT1KpHpQwnbuNRTK3vTbQyx4pB6mwBmZQQAfLpIJ3+854VDMktcUyVfrVLxZaWpLx72 Cnmw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=i8Z9JW71iuJMVJKowo55YUhlmbC60cA0lzzprLCJ5rA=; b=CzKv35r8b98Xg9VPD5og6DVyXxwfIsCHO4OtSb5EZUpPoOQ+eBf5VX6i/ZiTdbp/pl G0bVGGWxin/zpr8f7I/OqfwuLIaT+GC9GXdXT/M9VTmQZMO0oNkLpulKglO93oLAfYRp WoyC4DvKnFmnFvo55L3qW/S+RAqoJAlO+kpU8qSsxZyRCtU8w4KiSImcvbF5fLJqOwvi wijOeP6GhhDrWoGUbe8xV66yCppCknUVjFyUGdEMjNrzrkyQVqpq1pw9HQQlut6QAKCI GL/lsfkSizvRqHRimkGlMeECuKI0w6a5C+w7AM92R88M0CQmM3Lm1iVMy3Uzq9Qz5Oqr ZzwQ== X-Gm-Message-State: AOAM530Hafcwcz+F/u1HlTFd4FsMoKtwnQ1RukY2ucFh06L/z557AOE9 vM5lOq2yzBnBrVG7TCpyt9z/bx4Xnh5MFnA2dPpAzsuou2U= X-Google-Smtp-Source: ABdhPJzRHXV16oFpYM4KaU6bp1LDzNATrVMn6k0+2S7HD5A8Xt4I4g8umnFeYXiMMra3StqNCw/OEcU0zyCZRAeMLE0= X-Received: by 2002:a17:90a:454a:b0:1ca:91c7:df66 with SMTP id r10-20020a17090a454a00b001ca91c7df66mr32770533pjm.186.1649623308994; Sun, 10 Apr 2022 13:41:48 -0700 (PDT) MIME-Version: 1.0 References: <20220410171422.600D018C0D5@mercury.lcs.mit.edu> In-Reply-To: <20220410171422.600D018C0D5@mercury.lcs.mit.edu> From: John Cowan Date: Sun, 10 Apr 2022 16:41:36 -0400 Message-ID: To: Noel Chiappa Content-Type: multipart/alternative; boundary="00000000000058a3c705dc52db9c" Subject: Re: [TUHS] Interesting commentary on Unix from Multicians. 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: TUHS main list Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" --00000000000058a3c705dc52db9c Content-Type: text/plain; charset="UTF-8" On Sun, Apr 10, 2022 at 1:18 PM Noel Chiappa wrote: > Unix had (and still may have, I'm not up on Linux, etc) a really major, > hard > boundary beween 'user' code, in processes,and the kernel. There are > 'instructions' that invoke system primitives - but not too many, and > limited > interactions across that boundary. So, restricted semantics. > The same is true for the more recent Unix variants, modulo a few special cases such as Larry mentions, but broadly speaking userland and the kernel are still separated. > Imagine building a > large application which had a hard boundary across the middle of it, with > extremely limited interactions across the boundary. > You mean like the Web? :-) In 2000-2005 I wrote a substantial quasi-batch application that supported $EMPLOYER's main product and was written about half in shell scripts and half in Perl, or more accurately entirely in shell scripts, but if I needed a pipeline component that wasn't already available in SunOS or as third-party open source, I wrote it in Perl. (There was a single 10-line C program to eliminate a performance bottleneck.) So the application as a whole was full of hard boundaries across which nothing could pass except text streams; I found that this added substantially to its debuggability and maintainability. --00000000000058a3c705dc52db9c Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable


On Sun, Apr 10, 2= 022 at 1:18 PM Noel Chiappa <= jnc@mercury.lcs.mit.edu> wrote:
=C2=A0=C2=A0
Unix had (and still may have, I'm not up on Linux, etc) a really major,= hard
boundary beween 'user' code, in processes,and the kernel. There are=
'instructions' that invoke system primitives - but not too many, an= d limited
interactions across that boundary. So, restricted semantics.

The same is true for the more re= cent Unix variants, modulo a few special cases such as Larry mentions, but = broadly speaking userland and the kernel are still separated.
I= magine building a
large application which had a hard boundary across the middle of it, with extremely limited interactions across the boundary.
You mean like the Web?=C2=A0 :-)

In 2000-2005 I w= rote a substantial quasi-batch application that supported $EMPLOYER's m= ain product and was written about half in shell scripts and half in Perl, o= r more accurately entirely in shell scripts, but if I needed a pipeline com= ponent that wasn't already available in SunOS or as third-party open so= urce, I wrote it in Perl.=C2=A0 (There was a single 10-line C program to el= iminate a performance bottleneck.)=C2=A0 So the application as a whole was = full of hard boundaries across which nothing could pass except text streams= ; I found that this added substantially to its debuggability and maintainab= ility.
--00000000000058a3c705dc52db9c--