From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,5ac12f5a60b1bfe X-Google-Attributes: gid103376,public X-Google-Thread: 101deb,f96f757d5586710a X-Google-Attributes: gid101deb,public X-Google-Thread: f43e6,5ac12f5a60b1bfe X-Google-Attributes: gidf43e6,public From: kbradley@us.oracle.com (Kirk Bradley) Subject: Re: Ariane 5 - not an exception? Date: 1996/08/13 Message-ID: #1/1 X-Deja-AN: 174034293 references: <4t9vdg$jfb@goanna.cs.rmit.edu.au> <4tiu6e$kpm@news2.cais.com> <4up8pi$lvi@goanna.cs.rmit.edu.au> <32106B34.57DB@lmtas.lmco.com> content-type: text/plain; charset=ISO-8859-1 organization: Oracle Corporation: Mainframe and Integration Technologies mime-version: 1.0 newsgroups: comp.software-eng,comp.lang.ada,comp.lang.pl1 Date: 1996-08-13T00:00:00+00:00 List-Id: Why do you say that PL/I has no signalling facility. What do you call ON units? how do they get triggered? I'd say it for sure has signalling In article <32106B34.57DB@lmtas.lmco.com>, Ken Garlington wrote: > ++ robin wrote: > > > > > 2) PL/I > > > > > a) There is no PL/I compiler for the 1750A > > > > ---Not an obstacle. How was an Ada compiler written for it? > > I believe an existing one was purchased. I don't believe an Ada > compiler was written specifically for the Ariane SRI, as apparently > you are suggesting be done for PL/I. How would your argument about > mature PL/I compliers stand up in the face of a requirement to > develop a brand-new compiler for a new target? > > > > > > b) Ada is far more suitable for safety-sensitive software than Pl/I > > > > ---Nonsense. PL/I has a long (30 years) record in > > excellent real-time facilities, and with people with > > experience in error-recovery and fail-soft in routine > > commercial applications as well as real-time programming. > > It must be the lag in these newsgroups. I've posted more than one > request in comp.lang.pl1 for some examples of PL/I's use in safety-critical > real-time flight software, and narya a taker yet. I look forward to > some examples... > > Perhaps those people are too busy building such software to read > the Internet? > > > > c) This failure was not a language issue. > > > > ---Isn't it? One of the arguments put forward was that > > an Ada condition couldn't be raised and leave a trace, > > and that it would be argued that there was no guarantee > > whether a piece of code was executed. > > That argument could be put forth, but of course it would be false. > We routinely trace Ada 83 exceptions in our debugging environments. > Ada 95 also adds a standardized capability to annotate exceptions with > user-defined information. > > > In PL/I, a SIGNAL statement (which can be used for > > program checkout) leaves a printed record that it was > > executed. It gives a message that the condition was > > raised, and comes with line numbers, etc. There is > > absolutely no doubt that the statement did not execute! > > There is no SIGNAL statement in PL/I. In fact, PL/I has no > exception handling capabilities. (I figure, since ++robin can > continue to ignore the capabilities of Ada, why shouldn't we > ignore his claims as to the capabilities of PL/I)? > > As a side issue: Could someone post the printer port address for the > Ariane SRI? Most of our IRSs don't have a printer attachment. > Must be something those experienced PL/I programmers demand be > added to the hardware... :) > > > > > > But > > > stupid management is something no programming language can change. > > > Given other engineering constraints on this project, Ada is really > > > the only reasonable language to choose. > > > > ---Scarcely convincing, in view of the failure. > > Again, I would be more convinced of _your_ arguments if you would post some > of the flight software items you've developed in PL/I. For some reason, > this request keeps getting lost in the newsgroup. Until then, I think I'll > just enjoy the speculation... > > -- > LMTAS - "Our Brand Means Quality"