Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!husc6!mit-eddie!minya!jc From: jc@minya.UUCP (John Chambers) Newsgroups: comp.cog-eng Subject: Re: Request for human interface design anecdotes Message-ID: <410@minya.UUCP> Date: Sun, 22-Nov-87 18:33:08 EST Article-I.D.: minya.410 Posted: Sun Nov 22 18:33:08 1987 Date-Received: Wed, 25-Nov-87 03:28:25 EST References: <1721@spar.SPAR.SLB.COM> <1621@megatest.UUCP> <101@ateng.UUCP> <6690@brl-smoke.ARPA> Organization: home Lines: 76 In article <6690@brl-smoke.ARPA>, gwyn@brl-smoke.ARPA (Doug Gwyn ) writes: > In article <1689@rayssd.RAY.COM> dhb@rayssd.RAY.COM (David H. Brierley) writes: > >If users removing all of their files by inadvertently typing "rm *" is > >a habitual problem at your site, why not make the command default to > >interactive mode? > > Please don't fuck with the standard commands. If you're going to > change the semantics, give it a new name and retain the old one > for applications that expect the documented semantics. I'll second that. Back in high-school shop, it was common to point out to the students that there were a lot of very dangerous tools around. Most of them had some sort of safety shields. The teachers commented that professionals usually took the shields off in their own shops, as they interfere with efficient use (and sometimes damage the material). But we weren't professionals; we would leave the shields on. The computer field hasn't learned this lesson. Among all the clumsy and difficult-to-use operating systems, we have Unix as one of the few examples of a system designed by and for professionals. But we somehow insist on handing the raw, unshielded tools (like rm) to pros and novices alike. If we had the sense of the average high-school shop instructor, we would realize that novice users shouldn't be handed sharp tools like rm. We would supply them with things like the Macintosh's trash cans or VMS's versions or some sort of protection. But we would at the same time realize that the professionals among us want and need good tools for doing their jobs, and the bare, unshielded tools are right for them. Unix can support this sort of stuff easily. I've done it on lots of systems. Unlike some other systems, there is no problem with providing multiple libraries (and multiple command languages) that are "friendly" to multiple classes of users. Implementing "delete" by renaming is quite trivial. Implementing multiple versions of files is also quite trivial. If a script isn't fast enough, these are easily coded in C. There is little point in modifying a command like 'rm' to be friendly to novices. For non-hackers, this is the wrong name. If you are going to build safety features in, you should at the same time pick a new, user-friendly name such as 'delete'. In that way, you will help the novice users, and you won't mess up any of the thousands of scripts floating around that need rm to get their job done. One thing we certainly don't need is to discover that all our carefully tailored, user-friendly scripts are now asking the hapless user if he really wants to "rm /tmp/vSl5437a". And when my script decides to clean up the garbage in its scratch directory, it is decidedly unfriendly to have the user forced to verify the "rm *" when he doesn't even know that the directory exists. It is also unfriendly to me to force me to go through old scripts and change the calls on things like rm because some turkey decided to make it more friendly to novices. I like Unix's terse, powerful commands. They're just what I need to get a lot of work done easily. Please don't mess them up in a misguided effort to save some novices a bit of heartbreak. You'd be doing them and me a big favor by implementing a new command that does their job right, and leaves me with my sharp tool. BTW, I also have some very sharp knives in my kitchen. Like most parents, when there were toddlers around, I kept them well off the floor. Now that the toddlers are in high school, I feel free to keep some of them on a lower shelf. I have no intention of ever replacing them with "safe" knives, even if I do nick myself once in a great while. [I've taken the liberty of responding only in comp.cog-eng; groups like unix.wizards shouldn't be harassed by stuff like this. Maybe some of the usenet admins out there should try to get this discussion out of the irrelevant newsgroups.] -- John Chambers <{adelie,ima,maynard,mit-eddie}!minya!{jc,root}> (617/484-6393)