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=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,5bcf30769d6d9599 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-08-27 10:16:37 PST Path: archiver1.google.com!newsfeed.google.com!sn-xit-02!supernews.com!newsfeed.direct.ca!look.ca!news1.tor.metronet.ca!nnrp1.tor.metronet.ca!not-for-mail Message-ID: <3B8A8073.6010503@home.com> From: "Warren W. Gay VE3WWG" User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:0.9.2) Gecko/20010726 Netscape6/6.1 X-Accept-Language: en-us MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: ADA os talk References: <20010826235613.1b22c8c2.tonygair@kissmyspam.blueyonder.co.uk> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Date: Mon, 27 Aug 2001 17:16:36 GMT NNTP-Posting-Host: 198.96.47.195 NNTP-Posting-Date: Mon, 27 Aug 2001 11:16:36 MDT Organization: MetroNet Communications Group Inc. Xref: archiver1.google.com comp.lang.ada:12469 Date: 2001-08-27T17:16:36+00:00 List-Id: chris.danx wrote: > "Tony Gair" wrote in message > news:20010826235613.1b22c8c2.tonygair@kissmyspam.blueyonder.co.uk... >>This is an area I've been watching for some time. >>And I suspect a lot of people are interested in this too..... >>I would be interested to know peoples strategies for getting one up and > running and just to get the talk rolling heres my tuppence.. > >>Make a ada kernal and interface it to the rest of linux operating system >> by using c interfaces and then start writing the filesystem, drivers and X >> windows, blah blah.... > >>what do people think ??? > > There are two on going OS in Ada developments that I know of at the minute > (of the Desktop variety). AdaOS and my own -- Sorcerer. Ada OS is > seemingly stalled and my own progresses very slowly mainly due to two > factors: my interest in a quality IDE in Ada which is in development and the > learning curve involved in OS development. There is at least one more being developed in France. The name of it escapes me at the moment. I believe there are others, including IIRC, one in Germany. ... > My suggestion is to start designing and coding file system drivers... You > can design and code them almost immediately and if the project goes > pear-shaped then at least you can make them available for other ppl to play > with. Start with a file and pretend it's an FS in itself, write a disk-like > interface for manipulating the file, then write all the code on top of this. I think a lot of people could benefit, just from seeing what has been "done before". For example, the following site lists several research papers on various O/S projects to date : http://www.cs.arizona.edu/people/bridges/oses.html Its surprising to see how many ideas that you thought were original, which already have been researched by someone else ;-) If you don't start there, you're quitely likely duplicate some effort, and very certainly, won't learn from their mistakes without expending considerable effort. Since it is the "considerable effort" that kills most projects, it seems that this should be the first step. > At the same time, slowly begin to play with pmode or whatever it is on your > target machine, and learn the concepts of OSes. Only when you've learned > about such things should you even think about designing the OS, never mind > coding it. And don't have more than 2 or 3 developers to start with. > Anymore than that and the project is likely to go belly up. I have begun looking at the exokernel designs recently. I find them intriguing because their design is such that the kernel is just a safe shell around the physical resources. Then you build your abstraction layer on top of that. This helps to divide the project into manageable components. It's main advantage is that you can build several different abstractions on top of the same "base". The following is a one good place to start: http://www.pdos.lcs.mit.edu/exo.html It may be that there is an existing exokernel design that can be used as a starting point for an Ada OS design. Later a fully Ada "base" can then be developed if necessary, once some experience has been gained at the "higher layers". -- Warren W. Gay VE3WWG http://members.home.net/ve3wwg