Re: Ada-inspired OS/Language

[nickroberts@blueyonder.co.uk (Nick Roberts)]

On Tue, 20 Aug 2002 13:57:24 -0400, "Warren W. Gay VE3WWG"
<ve3wwg@cogeco.ca> strongly typed:

>Ryan wrote:
>> An article on Slashdot reads
>> (http://developers.slashdot.org/article.pl?sid=02/08/18/2053259)
>...
>> "BRiX, unlike other modern operating systems, does not use hardware to 
>> isolate and protect applications from each other. Instead, it uses a 
>> single address space and relies on a safe-language to generate code that 
>> will not access memory for which it does not own. 
>
>Here we go again.. another DOS-like, memory wide open to corruption
>concept. PC's eventually, with the help of 286 and later got to the
>point where they could protect processes. Now we've regressed with
>the palms etc., back to this no-protection model. No matter how good
>the language is, there will always be occaisions where one process
>steps on another unless it is prevented from doing so in hardware.
>
>This is OK for research. Not good for running systems that must
>run as firewalls, or central hosts to university students!

This is one reason why BRiX (or Oberon) will not have a tremendous effect
on the design of AdaOS.

The other main reason is that this type of design appears to preclude the
possibility of the direct execution of programs imported in machine code
form. I find this an unacceptable restriction, and I think too many users
would as well.

By the way, there is a simple overview of AdaOS now available at

http://www.adaos.net

with a pretty diagram if anybody is interested.

-- 
Nick Roberts