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=-0.4 required=5.0 tests=AC_FROM_MANY_DOTS,BAYES_00, LOTS_OF_MONEY autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,958ed45cc4906b53 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-07-31 12:24:15 PST Path: archiver1.google.com!newsfeed.google.com!newsfeed.stanford.edu!newsfeeds.belnet.be!news.belnet.be!psinet-eu-nl!psiuk-p4!uknet!psiuk-n!news.pace.co.uk!nh.pace.co.uk!not-for-mail From: "Marin David Condic" Newsgroups: comp.lang.ada Subject: Re: Distributed system portability Date: Tue, 31 Jul 2001 14:55:14 -0400 Organization: Posted on a server owned by Pace Micro Technology plc Message-ID: <9k6uuk$qb$1@nh.pace.co.uk> References: NNTP-Posting-Host: 136.170.200.133 X-Trace: nh.pace.co.uk 996605716 843 136.170.200.133 (31 Jul 2001 18:55:16 GMT) X-Complaints-To: newsmaster@news.cam.pace.co.uk NNTP-Posting-Date: 31 Jul 2001 18:55:16 GMT X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Xref: archiver1.google.com comp.lang.ada:10889 Date: 2001-07-31T18:55:16+00:00 List-Id: That might or might not work, depending on what your requirements are for the external representation of the data. If you define the whole thing yourself, then whatever way you output the data is the way you input the data & defining the operations for the primitive types is (probably) good enough. However, you *could* be in trouble if there are requirements to traverse byte boundaries or find things in the middle of words or otherwise have to do something "wierd". You might also discover that this whole thing can get rather painful if you have lots of user defined primitive types. I've seen messages defined in systems that aren't easily dealt with via the Stream attributes. If you're limiting yourself to a subset of the possible representations of messages in a stream, you can get by, but if you have to deal with all of the possibilities it gets complicated. MDC -- Marin David Condic Senior Software Engineer Pace Micro Technology Americas www.pacemicro.com Enabling the digital revolution e-Mail: marin.condic@pacemicro.com Web: http://www.mcondic.com/ wrote in message news:QAC97.18171$Kd7.10872006@news1.rdc1.sfba.home.com... > >you have to do *all* this (including implementing all the stream attributes for > >*all* types that will ever be used with the stream, excepting perhaps some > >composite types). With that much work involved, the streams aren't really > >providing you much except the supposedly nice syntax. > (I haven't tried this but ...) I think you just have to implement the > base types, and you need do it only once. So if you are going to be > doing a lot of systems where data goes between a machine of type A and > another B with different architecture or compiler, you can implement > integer'read etc just once, and all your different programs can use it > for integers ... composite types. Isn't that in fact done for the > Gnat distributed systems implementation?