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-Thread: 103376,382fcf8feeefdd50 X-Google-Thread: f4fd2,9019ec15d661ad71 X-Google-Attributes: gid103376,gidf4fd2,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news2.google.com!news3.google.com!feeder1-2.proxad.net!proxad.net!feeder2-2.proxad.net!cleanfeed1-b.proxad.net!nnrp15-1.free.fr!not-for-mail Newsgroups: comp.lang.ada,comp.lang.lisp Subject: Re: computer language used to program Mars Lander Face: iVBORw0KGgoAAAANSUhEUgAAADAAAAAwAQMAAABtzGvEAAAABlBMVEUAAAD///+l2Z/dAAAA oElEQVR4nK3OsRHCMAwF0O8YQufUNIQRGIAja9CxSA55AxZgFO4coMgYrEDDQZWPIlNAjwq9 033pbOBPtbXuB6PKNBn5gZkhGa86Z4x2wE67O+06WxGD/HCOGR0deY3f9Ijwwt7rNGNf6Oac l/GuZTF1wFGKiYYHKSFAkjIo1b6sCYS1sVmFhhhahKQssRjRT90ITWUk6vvK3RsPGs+M1RuR mV+hO/VvFAAAAABJRU5ErkJggg== X-Accept-Language: fr, es, en X-Disabled: X-No-Archive: no References: <185ee7f9-9d4f-4f49-8dbe-6b623b8a8223@c58g2000hsc.googlegroups.com> <887fc0a7-0a5a-4d2e-a9ea-eb9e32d6a818@m36g2000hse.googlegroups.com> <807ef880-b2ac-4ac6-877c-21274e8ff4ab@d77g2000hsb.googlegroups.com> <26ec19b4-09fc-405b-a188-57b6ee5ca1a3@k36g2000pri.googlegroups.com> From: pjb@informatimago.com (Pascal J. Bourguignon) Importance: high Organization: Anevia SAS User-Agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/22.1 (gnu/linux) Date: Thu, 24 Jul 2008 11:04:47 +0200 Message-ID: <7cprp3tzyo.fsf@pbourguignon.anevia.com> Cancel-Lock: sha1:Yzc5ZTkwZTg3ZGQ4Y2M2YjhkMDk4Nzc3NWEwNDc4OWQ3YTFlOTJmNA== MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii NNTP-Posting-Date: 24 Jul 2008 11:04:59 MEST NNTP-Posting-Host: 88.170.236.224 X-Trace: 1216890299 news-2.free.fr 20778 88.170.236.224:57055 X-Complaints-To: abuse@proxad.net Xref: g2news2.google.com comp.lang.ada:7032 comp.lang.lisp:30619 Date: 2008-07-24T11:04:59+02:00 List-Id: "jhc0033@gmail.com" writes: > On Jul 23, 7:43 am, Michael Oswald wrote: >> I mean, I work in the space >> business (although not directly on on-board software but rather mission >> control software and testing equipment) but I haven't heard of Lisp >> usage. Would definitely be a 'nice to know' for me. > > Probably because they weren't too successful. I personally think Lisp > is super-cool, but inappropriate for space (or any reliability- > sensitive work). > > If I remember correctly, when they used Lisp in the probe, there was a > bug and they used Lisp's live patching and interactive debugging to > fix it, so they only missed their target by a quadrillion miles > instead of missing it by a gazillion miles. It wasn't the purpose of the mission to hit the target, but to fly by. > On the other hand, the bug wouldn't have happened in the first place, > if they used a good static language. I'll let someone who knows better > fill in the details (that's why I added comp.lang.lisp to the groups) > > Happy space exploration and exploitation! http://en.wikipedia.org/wiki/Deep_Space_1 http://www.nasa.gov/lb/centers/ames/news/releases/1999/99_37AR.html REMOTE AGENT EXPERIMENT MEETS ALL OBJECTIVES http://web.archive.org/web/20010923215958/http://rax.arc.nasa.gov/ http://www.flownet.com/gat/jpl-lisp.html Be sure to read the description of the bug: http://web.archive.org/web/20061106012026/http://ic.arc.nasa.gov/publications/pdf/2000-0176.pdf It has nothing to do with Lisp per se. It could have occured with any other programming language. Now, the question is how do you correct a dead-lock on a running system compiled from Ada code, 3 second-light away, without rebooting it? This is what lisp allowed for this space probe, and what lisp allows also for running web servers. -- __Pascal Bourguignon__