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From: jc@minya.UUCP (John Chambers)
Newsgroups: comp.unix.wizards
Subject: Re: Request for human interface design anecdotes
Message-ID: <407@minya.UUCP>
Date: Sat, 21-Nov-87 09:47:43 EST
Article-I.D.: minya.407
Posted: Sat Nov 21 09:47:43 1987
Date-Received: Mon, 23-Nov-87 04:13:46 EST
References: <1721@spar.SPAR.SLB.COM> <1621@megatest.UUCP> <101@ateng.UUCP> <1402@cuuxb.ATT.COM>
Organization: home
Lines: 61
Summary: KISS...

> This  request  has  spawned  many  stories  involving  rm  *  (or
> variants)  that were not intentional.  
> 
> Then there was the time we did rm -rf ../*
> 
> The moral of this is that the command  interpreters  need  to  be
> modified 

Well, I hate to be a wet blanket (sure, sure; ya love it; admit it :-),
but I've never typed anything like this.  What I have typed a *lot* of
is 'y' to silly suggestions that I don't know what I'm doing.  This has
wasted a lot of my time.

One of the first things that impressed me when I first snuck onto a
Unix system 'way back when was that, unlike all the other systems I'd
ever used, Unix actually did what I told it to do.  It didn't harass
me, question my intelligence, or anything like that.  When I typed
"rm *", it did it.

Nowadays, it has gotten recalcitrant, and I have to say, in effect,
"Of course, I want that file rm'ed; that's what I said, wasn't it?"
While I've grown in experience, Unix has taken to treating me as
a child who needs his hand held.

When I was in High School, most of the power tools in the shops had
various shields and safety features.  The intructors sometimes pointed
out that professionals would routinely remove the shields.  But that
was after they had learned a certain respect for the tools, and also
after they had learned work techniques that made the tools safe for
them.  On the other hand, such professionals didn't allow children
(or unqualified adults) into their workshops.

This could be well applied to computer systems.  Unix, like any good
tookbox, requires power tools like rm.  Professionals want such tools
without safeguards.  But you don't hand them to novices.  Anyone who
hands a "bare" Unix to a novice, and teaches him/her to type "rm *.o",
is doing the equivalent of teaching someone to use a circular saw with
no shield or goggles.  Novices should not be taught about rm, but about
other tools (say, a simple script or alias called 'del') that asks the
right questions.  After they express frustration with such safeguards,
or when they need to write a script that doesn't harass its users, they
can be told "Well, there's this other library command 'rm'...".

I guess this is a complain about the fact that we have a nicely layered
system; its designers carefully explained to us all about this; we don't
listen.  The Unix community gets criticised for giving novices a command
language (sh) that was intended for system developers.  But Unix has a
perfectly good method of giving non-hackers their own user-friendly shells;
why do we teach them to use sh?  It is trivial to add a library script
that 'removes' files by renaming them; why don't we do it?  It is trivial
to say "ln /bin/cat /bin/type"; why don't we do it?

My claim is that Unix in fact has a good design for user-friendliness;
the problem is vendors and system developers that violate the design by
using low-level tools like rm at a higher (user) level.

'Nuf preaching for now; this oughta get me lots flames to while away
the hours reading...

-- 
John Chambers <{adelie,ima,maynard,mit-eddie}!minya!{jc,root}> (617/484-6393)