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=unavailable autolearn_force=no version=3.4.4 Path: eternal-september.org!reader01.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED.i6Yi6ZHSMX5yC+jErMXNlA.user.gioia.aioe.org!not-for-mail From: russ lyttle Newsgroups: comp.lang.ada Subject: Re: Why couldn't an operating system be written in ada Date: Sun, 24 Feb 2019 21:25:22 -0500 Organization: Aioe.org NNTP Server Message-ID: References: <4s8rud$9j3@tribune> <6ee2838d-4b6a-4b8e-9583-fc1ce4f3a1bd@googlegroups.com> NNTP-Posting-Host: i6Yi6ZHSMX5yC+jErMXNlA.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 X-Notice: Filtered by postfilter v. 0.9.2 Content-Language: en-US Xref: reader01.eternal-september.org comp.lang.ada:55649 Date: 2019-02-24T21:25:22-05:00 List-Id: On 1/14/19 6:26 AM, George Shapovalov wrote: > Well, gnat is built on top of gcc, so you have implicit Ada integration with the gcc toolchain and even Posix bindings to assist is some tasks. So, strictly speaking, nothing stops someone from starting to replace Linux/BSD kernel internals one module at a time :) (you would have, of course, to operate within the no-RTL limitation). Having maintained gnat in Gentoo Linux I can attest to feasibility of at least small tweaks and general compatibility.. > Of course you would have to prove the merit of such replacement to the larger community, presenting extra stability/maintainability or utility sufficient to overcome the resistance to the unknown new thing. > > Also, @Pascal Martin mentions some very nice points about tasking and heap management. Unix has a different tasking model, so direct substitution is not an option, but I suppose a superset and bindings could be provided. This and all others are, however, tedious and time consuming tasks. Especially the community handling aspect. But at least this way you have some "point of entry". Creating a complete new and not tied to established standards OS may be possible (even if resource hungry). But making people actually use it (to any significant extent, rather than playing with it for all of 1hr, even when provided for free) would be much more complicated.. > Actually, I once wrote a small operating system in ada'83. I was just about to ask here if someone had done the same thing in a more modern version. Think of an Ada version of uCOS. A generic cross-compiler or IDE that accepts a profile of the target hardware might be needed.