Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!sq!msb From: msb@sq.UUCP Newsgroups: comp.cog-eng,comp.unix.xenix,comp.unix.wizards Subject: Re: Request for human interface design anecdotes (and a cure?) Message-ID: <1987Nov27.011955.10801@sq.uucp> Date: Fri, 27-Nov-87 01:19:55 EST Article-I.D.: sq.1987Nov27.011955.10801 Posted: Fri Nov 27 01:19:55 1987 Date-Received: Sun, 29-Nov-87 14:37:51 EST References: <3103@psuvax1.psu.edu> <1987Nov21.014754.19660@sq.uucp> <392@xyzzy.UUCP> Reply-To: msb@sq.UUCP (Mark Brader) Organization: SoftQuad Inc., Toronto Lines: 39 Xref: sq comp.cog-eng:319 comp.unix.xenix:1063 comp.unix.wizards:5294 Checksum: 43319 Having had my knowledge of UNIX* insulted in public, I feel obliged to reply in public. This is positively my last posting on the topic. [And if you see it twice, it's not MY fault, I canceled the first one.] > >In short, the proper UNIX flavored method for protecting important files > >from "rm" is to turn off the write permission bit. > I'm sorry if that's what you want, because that's not what your system > is going to do. And then he quotes the V7 manual at me, and explains why permissions work as they do. Well, he should have read one more paragraph: # If the a file has no write permission and the standard input is a # terminal, its permissions are printed and a line is read from the # standard input. If that line begins with `y' the file is deleted, # otherwise the file remains... This is precisely the kind of interactive prompting that one school of "rm is too powerful" users like. But you only get it when you want it. Sure, write protecting the file doesn't affect what rm has *permission* to do ... it affects what it *will* do. As I said in my original posting, I do consider it a misfeature that if stdin is NOT a terminal then rm proceeds regardless of the file's permissions. I think the -f flag should be required in that mode also. (I also think that having said that should have been sufficient prevention from having UNIX basics explained to me on the net.) While I'm posting, I'll add the bit I left out the first time. I have made it a habit *not* to hit Return instantly upon typing a line that has both "rm" and "*" in it. I pause and reread it. It's an easy habit to establish, and it's all the protection I think I need against "rm * .o". Mark Brader "Male got pregnant -- on the first try." utzoo!sq!msb Newsweek article on high-tech conception msb@sq.com November 30, 1987 *"UNIX is a trademark of Bell Laboratories" is a religious incantation.