From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.5-pre1 (2020-06-20) on ip-172-31-74-118.ec2.internal X-Spam-Level: X-Spam-Status: No, score=-0.5 required=3.0 tests=BAYES_05 autolearn=ham autolearn_force=no version=3.4.5-pre1 Path: eternal-september.org!reader02.eternal-september.org!.POSTED!not-for-mail From: Brian Drummond Newsgroups: comp.lang.ada Subject: Re: is there a version of unix written in Ada Date: Thu, 1 Oct 2020 21:36:37 -0000 (UTC) Organization: A noiseless patient Spider Message-ID: References: <00cd3aaa-d518-43a2-b321-58d6fae70aebo@googlegroups.com> <57eb7a65-51ea-4624-b9dc-9c4dda0fee59n@googlegroups.com> <5f70fd3b$0$13541$426a74cc@news.free.fr> <87wo0d3iac.fsf@nightsong.com> <87sgb02l7b.fsf@nightsong.com> <875z7vyy1u.fsf@nightsong.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Date: Thu, 1 Oct 2020 21:36:37 -0000 (UTC) Injection-Info: reader02.eternal-september.org; posting-host="3724820f9e9805b4fd983d8626c05708"; logging-data="1026"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18j9V38sqIPtMJpCMcWgMNno5liXc/r2PM=" User-Agent: Pan/0.145 (Duplicitous mercenary valetism; d7e168a git.gnome.org/pan2) Cancel-Lock: sha1:+XFbx7yLdvynvQdlvIuiyWpS5Qw= Xref: reader02.eternal-september.org comp.lang.ada:60371 List-Id: On Wed, 30 Sep 2020 21:42:21 +0200, Dmitry A. Kazakov wrote: > On 30/09/2020 19:27, Paul Rubin wrote: >> "Dmitry A. Kazakov" writes: >>> OK, but that again is rather retrograde, MS-DOS pops into my mind >>> (:-)). >> >> MSDOS had no memory protection at all, and was basically single >> tasking. >> Singularity had the limitation that you were only allowed to use >> trusted compilers, but in exchange it gave an interesting approach to >> programming high performance multiprocessor systems. > > Put a trusted compiler into MS-DOS, where is a difference? Tasking would > be up to the compiler's run-time, obviously. > > I want an OS protecting from compilers I do not trust without > performance loss. Static checks must be enforced at run-time. Maybe I should knock together a new Linn Rekursiv on an FPGA. https://en.wikipedia.org/wiki/Rekursiv Objects were essentially memory segments, together with their own object number, type, size : static checks happened in parallel with operations. Even inheritance was handled below the instruction set level (in microcode) -- Brian