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From: george.priv@gmail.com
Newsgroups: comp.lang.ada,comp.lang.c
Subject: Re: computer language used to program Mars Lander
Date: Mon, 14 Jul 2008 08:31:38 -0700 (PDT)
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On Jul 14, 7:18 am, "jhc0...@gmail.com" <jhc0...@gmail.com> wrote:
> Interesting article I came across on Slashdot:
>
> http://developers.slashdot.org/developers/08/07/10/213211.shtml
>
> They are using C at JPL to program Mars Lander and just about
> everything now! Not Ada. Anyone got an explanation? I wonder also, do
> they really mean C++ when they say C. In my experience, this is a
> frequent, although disagreeable usage.

As pointed out it was subset of C and the size of the software is
relatively small by todays standards if it all fits in 128M (no VM
AFAIK).

The specifics of this project differs from earthly "life safety" type
of applications. If probe software fails, watchdog will reboot it into
the safe mode. There it will sit waiting the instructions/patches from
home.  Therefore, a critical part is a bootstrap and communication
module.  The rest is allowed to fail and can be fixed.

George