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 c211db4b for ; Sun, 4 Aug 2019 06:41:57 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id A29D79BA0F; Sun, 4 Aug 2019 16:41:55 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id DC5F69B84E; Sun, 4 Aug 2019 16:41:22 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id CBA4B9B84E; Sun, 4 Aug 2019 16:41:20 +1000 (AEST) Received: from freefriends.org (freefriends.org [96.88.95.60]) by minnie.tuhs.org (Postfix) with ESMTPS id 0DDD1948F2 for ; Sun, 4 Aug 2019 16:41:20 +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 x746emTs029043 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sun, 4 Aug 2019 00:40:49 -0600 Received: (from arnold@localhost) by freefriends.org (8.14.7/8.14.7/Submit) id x746elpl029042; Sun, 4 Aug 2019 00:40:47 -0600 From: arnold@skeeve.com Message-Id: <201908040640.x746elpl029042@freefriends.org> X-Authentication-Warning: frenzy.freefriends.org: arnold set sender to arnold@skeeve.com using -f Date: Sun, 04 Aug 2019 00:40:47 -0600 To: dot@dotat.at, arnold@skeeve.com References: <201908011235.x71CZP2B035023@tahoe.cs.Dartmouth.EDU> <201908020835.x728ZUal026532@freefriends.org> 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: Re: [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, doug@cs.dartmouth.edu Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" > arnold@skeeve.com wrote: > > 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. Tony Finch wrote: > When Bill Joy added the "multi-group stuff" to BSD all directories became > implicitly set-gid: Yes. But the commercial world had backwards compatibility to worry about. Thus the setgid bit on directories. I'm no longer sure who first came up with it. > As I understand it, when group support was improved in System V they did > not change creat() to match BSD but instead used the directory set-gid bit > to provide opt-in BSD semantics. I don't know if this was in Solaris or > earlier? Correct, but not sure when it was first done. > > > 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. > > BSD again :-) SCCS revision 6.6 so I think it appeared in 4.3BSD That sounds right. I stand corrected. Thanks, Arnold