From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from minnie.tuhs.org (minnie.tuhs.org [45.79.103.53]) by inbox.vuxu.org (OpenSMTPD) with ESMTP id 4e6f2086 for ; Fri, 2 Aug 2019 08:36:13 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id 5A0B29BAB4; Fri, 2 Aug 2019 18:36:12 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id BFE099BA7E; Fri, 2 Aug 2019 18:35:39 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id 6DBDB9BA7E; Fri, 2 Aug 2019 18:35:37 +1000 (AEST) Received: from freefriends.org (freefriends.org [96.88.95.60]) by minnie.tuhs.org (Postfix) with ESMTPS id A21349B84E for ; Fri, 2 Aug 2019 18:35:36 +1000 (AEST) X-Envelope-From: arnold@skeeve.com Received: from freefriends.org (freefriends.org [96.88.95.60]) by freefriends.org (8.14.7/8.14.7) with ESMTP id x728ZVxi026533 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 2 Aug 2019 02:35:31 -0600 Received: (from arnold@localhost) by freefriends.org (8.14.7/8.14.7/Submit) id x728ZUal026532; Fri, 2 Aug 2019 02:35:30 -0600 From: arnold@skeeve.com Message-Id: <201908020835.x728ZUal026532@freefriends.org> X-Authentication-Warning: frenzy.freefriends.org: arnold set sender to arnold@skeeve.com using -f Date: Fri, 02 Aug 2019 02:35:30 -0600 To: jpl.jpl@gmail.com, doug@cs.dartmouth.edu References: <201908011235.x71CZP2B035023@tahoe.cs.Dartmouth.EDU> In-Reply-To: User-Agent: Heirloom mailx 12.5 7/5/10 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Subject: [TUHS] Additional groups and additional directory permissions 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@tuhs.org Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" [Subject line changed] Hi. Doug McIlroy: > Yet clean as the idea of groups was, it has been used only sporadically > (in my experience). I suspect this was true mainly at Research, where the whole place was not large. Other people, as pointed out, found groups to be very useful. "John P. Linderman" wrote: > This changed when you > could be in multiple groups at the same time (a BSD invention?), Yes, at 4.2 BSD. The so-called group set. > and your > primary group automatically changed to the group owning your current > working directory (iff you belonged to that group). No. Your process simply carried around a bunch of groups with it, and if the group of the directory matched the primary group or a member of the group set, you got group permission. Arthur Krewat : > There's also the setgid bit on directories, that when files are created, > they will be in the group that the parent directory has on it. IIRC this was a Sun invention. It was in SunOS 4.x, and may even have been in SunOS 3.x. > Also, I don't think it's been mentioned, but there's the setuid bit on > directories - otherwise known as the sticky bit. When set, even if you > have rights to "write" the directory (meaning, delete files), you can't > delete those owned by other users. Useful for /tmp Also a SunOS invention, IIRC. > I have no idea what the timeline is for either of these features :) Timeline is late 80s, SunOS 4.0, I believe. (Larry? :-) These ideas later propogated into SVR4 / Solaris, Linux and most (if not all) the other proprietary Unixes. HTH, Arnold