OS design...

[Kragen]

On Mon, 19 Oct 1998, Ray Dillinger wrote:
> . . .
> 
> Also, I don't want to tie the system to my compiler's choices:
> three years from now I may learn something new and cool and
> change the way I implement procedure calls in my scheme
> compiler. When that happens, there are a bunch of things I don't
> want to break;  
> 
> 	1) Compiled code produced by earlier versions of the
> 		compiler.  A commercial application's customers
> 		don't always have the source lying around to
> 		recompile, and they may have very costly
> 		recertifications they'd prefer to avoid if 
> 		they do.  

If you were to build a system to Fare's specs, commercial applications
probably wouldn't be delivered as machine code, anyway.  They'd be
delivered in a form you could conveniently input to your trusted
compiler.

> If C++ were implemented by a system that compiles to LISP, then
> . . .
> You want to think about how silly the machine code would be if
> we compiled FORTH procedure calls to Scheme procedure calls??

It seems to me there must be a solution to this problem that doesn't
require going back to the level of machine code.  There are so many
nice things you get from having services accessible to procedure calls,
IPC by passing pointers, etc., that it seems a shame to give them up.

Kragen

-- 
<kragen@pobox.com>       Kragen Sitaker     <http://www.pobox.com/~kragen/>
A well designed system must take people into account.  . . .  It's hard to
build a system that provides strong authentication on top of systems that
can be penetrated by knowing someone's mother's maiden name.  -- Schneier