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.nBeL617r2Zbx34e1uUUY4w.user.gioia.aioe.org!not-for-mail From: lyttlec Newsgroups: comp.lang.ada Subject: Re: Why couldn't an operating system be written in ada Date: Tue, 26 Feb 2019 18:32:12 -0500 Organization: Aioe.org NNTP Server Message-ID: References: <4s8rud$9j3@tribune> <792fba1b-7a54-4d00-ae85-e6bd0737f001@googlegroups.com> NNTP-Posting-Host: nBeL617r2Zbx34e1uUUY4w.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 Openpgp: preference=signencrypt Autocrypt: addr=lyttlec@removegmail.com; keydata= xsFNBFk1VfQBEADVV619VW6hNAFg6ZMQbGXco7m1ILiJZAqmUXYndislpVFMTKfwupB1CnIC 5EPRwByXe7+JT4QHkxtPmbJT2pEfFvBvj9bYHuynWFHBAAWNGsZQR/82GZFE82Xv/yZZAhB0 yFKwObNYGyqukW+rGdJIzuURwniC7ZhQeC1OdBhxQ+wctPO057SfruOZvzMmR67FKuPRawO6 nh7mi3rLQDhe34EoNEX6GTh5mpwMZE1pjy2iMjQxWVXN0MmqaQBp1X6cUtUW1+cqO8XV5f1v q07q9YdNMhIiY06DPQS/41H7+OnZqr6Hhc5OfydMvKtI1G8bV9NRKf3IQl7kXMBcwmPMlwZB SwWSkLQroQvk+jDumtndRrdyoGIEIqYx/4ok48IiDLnxYX4O077xogGPxme7Vt/g9Pv+XHE5 1GyC4I1h6wvq9CUuVqS3ZAx2AVfN1NW7a8yN03hQNrdrhZXffk0M92Sk+f9Bc6UD0BELPDdu fdo55IsIca50qDjm4t5QteYlFSr7Frhmr/Q8nblMj/KkrW4uz8VphqMhYWheAwAgfTp2qGkM feb9+tI7AO8rxOy/0mfzYpJqP7OiA2rzL4icXob5ZFRcXgeVDORR5Cq+nr9c9Oj1GKjnWiVB 2Qu6CR31QyKhmwB6U14Q9ONHOQayRw7tbqBSdtisaFwA9ejTwQARAQABzR9ydXNzIGx5dHRs ZSA8bHl0dGxlY0BnbWFpbC5jb20+wsF9BBMBCAAnBQJZNVX0AhsjBQkJZgGABQsJCAcCBhUI CQoLAgQWAgMBAh4BAheAAAoJEKRFgqwK49Mum2AQAII8VA7PeLOvjuJ3TN6HYzn4JIO1TBnY VrWTM55O9aiRSA5YMy7TGmTHq9KSm/WYSgvKUTh0T1ujVl7+AzoSVS8D99fcRPTGdFUDYAzW zCFWQvCbPzOl5cYpycf40XpwA3vAIhAVX3zU3VtgI2BuxrTVg/GwdWHCg4l8ZjNJJQq9REuk MAzLbSKKcf6hUJp9gzEaJSRKtbeffuIlTUnHc/ewZE6BheFGvFM0qXuysc6nlsHNRiN0ESI+ ANJZrmVY0bl5QZ3sbXd+Sph7dfWyWSQFGIFaF9AK2nX/Vg0FJz0dnPqWZ8gGFmKOfdM1KH2G ZL2vee2vQPQkuH0+6kXEnlXVZ86fdNcFWdajEI1X9E9iE4XXKAgdWgr09ccO4dvfk1q4oSqy XZPI4HLYf2jPKiLjjTxRl27Zs+tHXESGHgtbzCVSzsuz+iRLX38T/TzcuxdT/tjTKHSwmoYm hXRDgm0A99uVv56MYG78xM2F7ke/FaEq8doxlmvdBE3B48U14MlWwXBIikKwwtSAc3aVylcq OG2jMiI0+Hl0h/GbibZjkgofAdAf5e4q8zCuU8xxJWyyl/yvb2alG5edvaHlYW1fonteoXRQ l8RxqSsVY9rP+wtGWFKcqso33KqJeNjROrcRwpRDrqPL8Rr5jLis0tqGO4f7vWtUQfJ3RwUJ sSXOzsFNBFk1VfQBEADIUSbxY2dwcKTuh6wFM4VKREj4fT184WojWSowxIemC0JPz01CEEo9 MqKX6Zbkm+H7d9oBy/PiZNgj5gptDgh5X1FVjZNDrc3zelYjMd7IpWANBJFgllFE1rSjFrfm p1YawRfV70KWF6/4ahNDIo7+KS2odO36XwxniUgh3FeLtA/RJ2yFXI0ZboDbq9wBgNnpl61H f97Z2S/6HU8nGd6yL3YXAOqtn2zwc+pWTNNzbGZWt5qp/cfLIBO7TJRgjzssrvERUxGPsN8D bZfCcn99diL7CPam+fzWklpgNNUa80AVC3PAjCmSUFV/byXabSfA2TF28SKyU/oEzIaQ4vm1 +MfxQYdO9a1ZoJF940quHI+vCIQeag0BsZQ/V19c+/SpHiU72XKPEN+5mBe88C24kswe7aQO XK2WH/lH216cD6izueDGxDtPGkaJVoeJQ0t6f2venVO555vpeuXOyXoCY191zwPsIsZIhj3v ZxtolwFVPAaDKLZ3KIon4lX/oh9+5+SCTYmtG43ygZf69XLdccaluDRMYQGMHrSN4pE+zTsW eCyMtTn1tnES6Kw5xMaLy375ESEUWZpN1RZmi0esxb7hbfuSHVfmGnqgAjKMR1iuE7tPwGAD i3FKi1MBkKbQ+voF2wCBqV4NkWdiiyPhvFo2hcM3lpw2YEanuuP7SQARAQABwsFlBBgBCAAP BQJZNVX0AhsMBQkJZgGAAAoJEKRFgqwK49Mu4jgQAM6BybV499Q7Df371Zu/XGgtElF7cjjk Vy44xa+o0k31ed6ScZ8e7isVEBtu400d2jNs4188kI6J+DGhdNtnMsqBjWuZXN4h7rh22IGO KLYOVVG72O5+8znZTsYW8ielLQEtlme6vBFn0tJo1tXX+8j23I4JEJCe/bBNuiOaG6QtLIIe SLOeUg4jiIl28BegSyG4qf2xci3RA/r+cWIiLfZWvjYOjWf//8AItki49YIezrPOtyOEnrWj wqqHRcay5nhqYPL/F4EJHqqObzupJknY2ng1O+UBWxGMD4ephLB2U/149MBcGv+9Iq6DCdBx X1xvEr85gnkIfxukSVQTSWoUy7rq6JULibXyB2h6rWoLqRvaP95UV8aLfGH8IdTXkOutJCuk a2749miM22zk1mXf0SbrQccqDR1xmMO/KdGRcCNMtTqV5PL/pXJkduFruwLhIVamEaYvUBAd 8PKiXL+c9ktaZLctK287o48Bh7UPUtTcHL3AdU7zpRDDmByzEE0iebDDhHRdz6ZRrolQDEen DmVhBWaJga2JwU+0lOcXu4S/nkAotI+YrgDpx/xHJ2XKm6l68FZEePi5/ChMEmggOhJ2N1IR RhgHfGvJCzwflitwlzpJRnqTzcxPnfxGDUau0W+yWApcxziLHLclm1hG7CzRcTKTxHl/kM6y c+mR Content-Language: en-US X-Notice: Filtered by postfilter v. 0.9.2 Xref: reader01.eternal-september.org comp.lang.ada:55683 Date: 2019-02-26T18:32:12-05:00 List-Id: On 2/26/19 4:30 AM, Dmitry A. Kazakov wrote: > On 2019-02-26 09:46, Niklas Holsti wrote: >> On 19-02-25 23:56 , Rabican wrote: >>> On Saturday, July 13, 1996 at 3:00:00 AM UTC-4, Mark  McKinney wrote: >>>> It has been claimed that the capability to interface with other >>>> languages >>>> is a great asset to ada. Sometimes interfacing can be a tremendous >>>> liability. Besides the OS could perform most of work that the language >>>> runtime does. So why not build an OS in ADA? >>> >>> yeah why not?  anything? >> >> This has been discussed many times before in comp.lang.ada. >> >> The first question is not "why not build an OS is Ada", the first >> question is "why build a new OS at all"? >> >> Then, if a new OS is going to be built for some reason, we can ask >> which language should be used, and of course (IMO) Ada would be a >> strong contender. However, for larger systems, the OS must usually >> implement a "process" concept that goes beyond Ada tasking and >> provides isolation between different users and applications. This >> means that the OS will have a process/service-level API that is not, >> as such, Ada-language specific. And so the fact that the OS is >> implemented in Ada becomes invisible on the application level. >> >> This is not to say that an OS API specified in Ada could not be an >> improvement (for Ada applications) on the current OS APIs which are >> usually specified in C. However, such an Ada OS API could also be >> provided for an OS implemented in C or some other language. > > Right. This is a general problem only tangentially related to Ada. The > purely procedural OS API outlived their time. > > A new generation of OSes must have higher-level API which would include > tasking and synchronization primitives as well as other abstract types > types. Call it OO or not, but that is beyond procedures, ints and void *. > > The world is not ready for this and the languages, Ada included, are not > mature enough either. > > So, yes, one can write an C-esque OS in Ada, but who needs yet another > horse cart? > Often overlooked is that any "C-esque" POSIX compliant OS turns the computer into a VAX. C was written to be easily translated into VAX machine code and POSIX signals are all the original interrupts on a VAX. If you have a CISC computer running VMS, C is your language.