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=-0.8 required=5.0 tests=BAYES_00,INVALID_DATE, MSGID_SHORT autolearn=no autolearn_force=no version=3.4.4 Path: utzoo!attcan!uunet!samsung!munnari.oz.au!bruce!goanna!ok From: ok@goanna.cs.rmit.oz.au (Richard A. O'Keefe) Newsgroups: comp.lang.ada Subject: Re: Ada tasking Message-ID: <3079@goanna.cs.rmit.oz.au> Date: 26 May 90 09:35:37 GMT References: <20075@grebyn.com> <1921@cod.NOSC.MIL> Organization: Comp Sci, RMIT, Melbourne, Australia List-Id: In article <1921@cod.NOSC.MIL>, sampson@cod.NOSC.MIL (Charles H. Sampson) writes: : In article <20075@grebyn.com> ted@grebyn.com (Ted Holden) writes: : >Tasking is naturally an operating system feature; ... : An interesting, unequivocal, statement. No "IMHO ...", no "Many people : think ..." Given that Ted Holden cited Hoare, I don't think it irrelevant to remind people who invented the CSP notation (which underlies occam, for example). That's right. Hoare. The last time I heard an argument like that, it was the Algol 60 committee saying that input/output was naturally an operating system feature. Algol 68 not only specified I/O, Algol 68 had a tasking model! It doesn't matter whether tasking is done with special syntax or by calling built-in procedures. If I can use it in a portable program, the effect of the tasking operations has to be defined _somewhere_. The fact that fork() and signal() and semop() and the rest are library functions in UNIX/C just means that (a) when I write a C program that needs IPC I have to look in a language manual _and_ a library manual and (b) my programs aren't portable. This is a help? The advantage of a separate tasking library is that several languages can use the same library. There's a lot to be said for that. But the point of Ada was to _reduce_ the need for using several languages. -- "A 7th class of programs, correct in every way, is believed to exist by a few computer scientists. However, no example could be found to include here."