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 autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 19584 invoked from network); 7 May 2022 20:10:35 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 7 May 2022 20:10:35 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id 43CF29CF58; Sun, 8 May 2022 06:10:34 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 2940B9CEEF; Sun, 8 May 2022 06:08:19 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="liFzWMXd"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 1DD2B9CEEF; Sun, 8 May 2022 05:57:43 +1000 (AEST) Received: from mail-lf1-f46.google.com (mail-lf1-f46.google.com [209.85.167.46]) by minnie.tuhs.org (Postfix) with ESMTPS id 09F569CEEE for ; Sun, 8 May 2022 05:57:42 +1000 (AEST) Received: by mail-lf1-f46.google.com with SMTP id w1so17653601lfa.4 for ; Sat, 07 May 2022 12:57:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=NkPfn7P96K+kSyPLeakEU3CVaTz9+y4lp0yQUxZzDwA=; b=liFzWMXdSq2TVTLMCIwA0yT4drF4bAsAKr++tu7NgmxBE2E1UmYnBzjqTZ8oLSAVku VRvShwpwQiXGpqMytfhuQCIjAt68QMrHW0TQwsapm4XqhVCWnUYBUmauvlKj4iq0r8Z3 zFN+Lj+ZA2BZxHUvl5ANCjr+PtpCTlCM010INAlO3f1wOg4JXrRSs1UJTT7nFP2vttAF 6heG7vr6xdwof6sYEf21q2n132iI/qrjOSKKWYnAYukOHlwsi11NCGXm8d98A5KbHEb4 WcNQy62VWC/wek3n6+zr2jo0IYL9wQQhqPvjguLpE1L64+MQlUqquXwRdvIfWhWx6Mee OLLw== 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=NkPfn7P96K+kSyPLeakEU3CVaTz9+y4lp0yQUxZzDwA=; b=Fx5/qN/6FrC1tAD9t6PXxoCWNCkLJez/rvvahFZAfJgmunGG2ZtfoJ9Zi+rZsyUlFC 7AitBwSE61xbpdmh6P7+qoGKgRk9UstBafqnDMDUHGOtEnbQJ72Rsm/h1lfhe0E5aDJB yHOFnYaTD+fN3H1iYzCZU36sgBVuP4OnHxGXvW8Vf3VNBV0p6ZUsav2c6qPnFCoKCHSh m6u3TVy/uDGCyflKpHYaAbGfgWN9pqMR759ermTb4NuTfnckm8Al7Bb2s5rQEY44tkAG feW2yy8FXvTqY4zlAmFIJf8b6e/YDwyzXnK9l06ZQHhUNw35BqMO/FbBiLJPsRMcW0Km vJwQ== X-Gm-Message-State: AOAM533+lezcU+RAlBdWJbVyb65YpyylsATSkiUCiwa7NxCzyza7Yo1X /br+JHfKqiBtXDRH610KJXmnzsfiNoL8M93KMNI= X-Google-Smtp-Source: ABdhPJzivyxoaOiKzPYbRhzzN2Nj+of/GZLymyHhdXi2J+pW6NzvUWGNSjPxH15oNCFLLIy8M4TcBWqH5L/ysVCv4Ws= X-Received: by 2002:ac2:596f:0:b0:472:5c36:17f5 with SMTP id h15-20020ac2596f000000b004725c3617f5mr7030786lfp.142.1651953460209; Sat, 07 May 2022 12:57:40 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: ron minnich Date: Sat, 7 May 2022 12:57:28 -0700 Message-ID: To: Warner Losh Content-Type: text/plain; charset="UTF-8" Subject: Re: [TUHS] conventions around zero padding in ip4 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" curiouser and curiouser, at least some Go packages parse it that way: rminnich@a300:~/go/src/github.com/u-root/u-root/cmds/core/ping$ cpu -key ~/.ssh/cpu_rsa 192.168.16 date Sat May 7 12:56:29 PM PDT 2022 rminnich@a300:~/go/src/github.com/u-root/u-root/cmds/core/ping$ cpu -key ~/.ssh/cpu_rsa 192.168.0.16 date Sat May 7 12:57:05 PM PDT 2022 rminnich@a300:~/go/src/github.com/u-root/u-root/cmds/core/ping$ [cpu is basically ssh with the plan 9 cpu command baked in, written in Go] So as a convention, it's been out and about for close to 40 years, many systems honor it, it seems not many people know of it, and not everything interprets it the same way. Huh! Well, you learn something new every day. I found it a wonderful shorthand when somebody showed it to me, and it's wired into my fingers at this point. I just assumed everyone else used it too. I may dig around and try to figure out when Plan 9 picked it up, that might give me some idea as to provenance. On Sat, May 7, 2022 at 12:50 PM ron minnich wrote: > > here's a simple example: > rminnich@a300:~/tamago/t9$ ping 127.1 > PING 127.1 (127.0.0.1) 56(84) bytes of data. > 64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.056 ms > > telnet 127.1 22 > Trying 127.0.0.1... > Connected to 127.1. > > All plan 9 programs I try parse 127.1 as 127.0.0.1 > > I first learned to use this convention in a BSD world, later on sunos. > > Interesting, the things you think are a standard, and are actually > just a convention! > > On Sat, May 7, 2022 at 12:15 PM Warner Losh wrote: > > > > > > > > On Sat, May 7, 2022 at 10:23 AM ron minnich wrote: > >> > >> IP4 padding came up recently: the ip command interprets 10.2 as > >> 10.2.0.0, whereas most things (golang libraries, ping, ...) interpret > >> it as 10.0.0.2. The latter interpretation accords with what I learned > >> 40y ago. > > > > > > 10.2 is ambiguous. In a network context, it means, typically, 10.2.0.0/16 (though your mileage may vary). > > In a host context, it means 10.0.0.2. It's this confusion that has lead to many efforts > > to outright kill this notation. > > > >> > >> But, I find myself wondering: where was the first use of the IP4 zero > >> padding convention? > > > > > > I know that it was around in the late 80s on TOPS-20 TCP/IP at Stanford, and in 4.2BSD (4.1c?). It may have also been in use at MIT. It's usage pre-dates my 1984 joining of the internet... > > > > Warner