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From: Jacob Sparre Andersen <sparre@nbi.dk>
Newsgroups: comp.lang.ada
Subject: Re: Has anyone tried Minix3 + Ada?
Date: Mon, 11 Jun 2012 08:45:01 +0200
Organization: Jacob Sparre Andersen Research & Innovation
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Date: 2012-06-11T08:45:01+02:00
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Patrick wrote:

> I am trying to learn more about how operating systems work. I am
> playing with Minix3. I have GCC 4.4 installed now but there is no Ada
> support. I might try to compile 4.7 with Ada support but I am
> concerned it will be futile.

Why?  IIRC Minix3 has a reasonably complete POSIX API, so I wouldn't
worry much about getting the GNAT runtime to compile.

> Assuming that I can cross compile GCC for Minix3, is there any reason
> Ada would not run on it?

Lacks in the Minix3 POSIX API.  But according to what I've heard, it
should be complete enough.

> Minix3 does not have kernel threads, the threading is in userland. I
> am wondering if tasking will work.

I'm pretty sure it will.

> Minix is also billed as a high reliability, embedded OS but I can't
> find any examples of it being used for this. Does anyone know if this
> is a proper claim or a goal?

I think it is a matter of your POV.  It is designed to be
"self-repairing".  The design of Minix3 means that you are likely to
have more context switches than with a more monolithic OS.  This again
means that it requires more resources.  Which turns into higher energy
consumption, which usually isn't popular for embedded applications.  I
doubt that Minix3 is easy to use for real-time tasks, due to the
large(r) number of processes involved in most OS activities.

Greetings,

Jacob (who hasn't tried Minix3 yet)
-- 
Never attribute to malice what can adequately be explained by incompetence.