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=-1.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 16527 invoked from network); 2 Jun 2020 18:54:34 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 2 Jun 2020 18:54:34 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id 002889CAD5; Wed, 3 Jun 2020 04:54:29 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id C34089CA44; Wed, 3 Jun 2020 04:54:03 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="tUeccEAv"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 637AA9CA44; Wed, 3 Jun 2020 04:54:01 +1000 (AEST) Received: from mail-vs1-f47.google.com (mail-vs1-f47.google.com [209.85.217.47]) by minnie.tuhs.org (Postfix) with ESMTPS id 02D6D9C96B for ; Wed, 3 Jun 2020 04:54:01 +1000 (AEST) Received: by mail-vs1-f47.google.com with SMTP id g129so2673811vsc.4 for ; Tue, 02 Jun 2020 11:54:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=C8IrGEQ4ecDJhjSLfxe0CupCd9MOMzsR7MSEg55oV1k=; b=tUeccEAvFa96HJ9FBj/t2rdaa7elYWteRaGeTGpjOjztT6KD7z8xnTosHZVn+yY3rz G9iTCPBtskVYou0EASWUrD7Ur7XVLQg/I46B0i/idjqQNFWgZFmNL0i6lK8aqH+SS5TK QnT7iLAycXoI6+Uh+S2yxhRr6fdLb0UF5hmty/XQ1agAE3RCHYFLLV7kQ5UvhmOI2BLd 79xEGc486bLcKIVlRKpk5r0LiMOJ+XD2lUppSLbYilbHXkXGv4y6lIknRC3SE9u72CVN u7iPsKWxN4xJHTouKZT2gbJWcH6jUmu3LQFVhXzPW6WSkichCApgAvxzcffFwESCx1cW oylg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=C8IrGEQ4ecDJhjSLfxe0CupCd9MOMzsR7MSEg55oV1k=; b=EWiZJmQEJCv3+Ww3jTcHoyC58+ax+4L6d/sHk66ME701Ab1TN6FTvw9wZnx/9O6lhY TU3q3Vb+o5X98glDTrJgyuMHwQyf9gToAxkMyNl3HY0WRyqvQF0rsUGCXtViuVUw59QL fGWQTlAe4mo1EkGRfZ86ZbeRClwQwb/fRKbc0dX/7yY6mKRFohpjBxtXUoYvATLU5rQD +ERSYs93HbG5o9j5NH0p1d5gH9PkPfi6E4yHswPetBPjcJFjEOMf7tRemKl+HuMUsHTA eZKwUJUW1D+a7breMy2Os8+ubFnPt0IWLH2gn81U7pMvGIR16ZPZC0H/YkUedy9OOxEh cQ5A== X-Gm-Message-State: AOAM533tFywRqPrqQrHilRjQ3+spJCjwL2LgiC2ASw9PPjkQDPTLUocE G9XS25jCfS85djZeLKEQlEriJU/lXWxAXVDF6P4iEA== X-Google-Smtp-Source: ABdhPJw04Tvllwjj6fY91g78qJ5xs/6OGd72vm/P/CtNqaDwRfaV5I0jb/yG8yX8rokP99MiKGikkkZ0TZdmLTDrYM4= X-Received: by 2002:a67:22c7:: with SMTP id i190mr5151675vsi.179.1591124040149; Tue, 02 Jun 2020 11:54:00 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:ab0:2b92:0:0:0:0:0 with HTTP; Tue, 2 Jun 2020 11:53:59 -0700 (PDT) In-Reply-To: <202006021759.052Hx5Et022619@freefriends.org> References: <202006021759.052Hx5Et022619@freefriends.org> From: Paul Winalski Date: Tue, 2 Jun 2020 14:53:59 -0400 Message-ID: To: arnold@skeeve.com Content-Type: text/plain; charset="UTF-8" Subject: Re: [TUHS] non-blocking IO 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@minnie.tuhs.org Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" On 6/2/20, arnold@skeeve.com wrote: > Paul Winalski wrote: > >> So I'm curious as to what the rationale was for Unix to have been >> designed with basic I/O being blocking rather than asynchronous. > > Also, the early Unixs were on smaller -11s, not the /45 or /70 with > split I&D space and the ability to address lost more RAM. I first encountered DOS/360 on a System/360 model 25 with 48K of memory. This was a one-job-at-a-time batch system, but the I/O primitive (EXCP--execute channel program) was asynchronous. So I don't think the small memory rationale really applies. -Paul W.