Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site watmum.UUCP Path: utzoo!watmath!watnot!watmum!cdshaw From: cdshaw@watmum.UUCP (Chris Shaw) Newsgroups: net.arch Subject: Re: What I miss in micro-processors (fairly long) Message-ID: <276@watmum.UUCP> Date: Fri, 27-Sep-85 15:47:16 EDT Article-I.D.: watmum.276 Posted: Fri Sep 27 15:47:16 1985 Date-Received: Sat, 28-Sep-85 06:39:47 EDT References: <796@kuling.UUCP> <2580002@csd2.UUCP> <191@graffiti.UUCP> Reply-To: cdshaw@watmum.UUCP (Chris Shaw) Organization: U of Waterloo, Ontario Lines: 40 In article <191@graffiti.UUCP> peter@graffiti.UUCP (Peter da Silva) writes: >> >> was it not the mariner probe that was lost due to a FORTRAN subscript error? >> >> I agree with you to a point. For low-risk code leave them out, But for my >> money I would prefer to see the code in for systems like nuclear plants, >> MX missiles etc.. > >What should the code do when a range-check occurs? Print out an error message >on ticker-tape & hang? Do nothing? A better analogy, perhaps, would be... > > "...like practicing sailing on shore with a mechanic [safety harness] >and leaving it on shore come the moment..." > >...you no longer have anything to attach them to. This seems to be a popular attitude... "we can't be bothered to think today, so we'll just assume that we can't think of ways to use range checking". Kinda dumb, don't you think? Someone mentioned calling ADA's exception package, which is probably a good thing. Another possibility (in the Mariner probe example) would be to "call home" if the exception package doesn't get the probe "out of the jam". If we're going to have an analogy fight, not having belts is like not telling a child what his home address/phone number is in case he gets lost. If the child gets lost, he's out of luck. If he has some information, (i.e. an exception handler) he may be able to find his way home none the worse for wear. Looking at Computer Science as mere programming as opposed to some branch of engineering is a "bad attitude", is unprofessional, etc. The problem, of course, is that not enough people see software tasks as warranting the ideals of Professional Engineering. Chris Shaw watmath!watmum!cdshaw or cdshaw@watmath University of Waterloo In doubt? Eat hot high-speed death -- the experts' choice in gastric vileness ! Brought to you by Super Global Mega Corp .com