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=-1.9 required=3.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.5-pre1 Path: eternal-september.org!reader02.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED.2uCIJahv+a4XEBqttj5Vkw.user.gioia.aioe.org!not-for-mail From: "Dmitry A. Kazakov" Newsgroups: comp.lang.ada Subject: Re: is there a version of unix written in Ada Date: Mon, 28 Sep 2020 09:41:23 +0200 Organization: Aioe.org NNTP Server Message-ID: References: <00cd3aaa-d518-43a2-b321-58d6fae70aebo@googlegroups.com> <57eb7a65-51ea-4624-b9dc-9c4dda0fee59n@googlegroups.com> <5f70fd3b$0$13541$426a74cc@news.free.fr> NNTP-Posting-Host: 2uCIJahv+a4XEBqttj5Vkw.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.3.0 Content-Language: en-US X-Notice: Filtered by postfilter v. 0.9.2 Xref: reader02.eternal-september.org comp.lang.ada:60302 List-Id: On 27/09/2020 22:59, DrPi wrote: > Le 27/09/2020 à 17:01, Dmitry A. Kazakov a écrit : >> An OS worth designing should be based on persistent objects and have >> no files and filesystem whatsoever. > ...one problem with this concept is you can't compile/run the huge > amount of existing software. You have to recreate everything. Unless you > have a comptibility layer for legacy software. 90% is garbage anyway, virtual machines are for the rest. BTW, regarding files the job of getting rid of them is basically done per using streams. >> On the programming language side, Ada requires a type system with >> visibility and privacy potentially done per hardware. >> >> Presently it is not possible to map private parts of a package and >> types declared there onto physically different memory pages protected >> from reading/writing in public view context. Calls to primitive >> operations cannot be routed through the kernel. Tasks and protected >> objects are not extensible. Without these OS API would rapidly degrade >> to low-level C-esque stuff. >> > This will make memory management very very complex. You want it in Ada or you want it in C with Ada syntax? To me a new OS must have new interface, which is a huge challenge, because interfaces of "modern" OSes are state of the art of late 70's. -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de