Date   : Tue, 23 Mar 1993 15:31:19 +0000 (GMT)
From   : "I Stephenson" <ian@...>
Subject: A new OS layer?

I've been thinking about what I get from my "REAL" computer systems Vs what 
I get from my BBC, and I think that the main problems (aside from lack of
speed and memory :-)) could be solved by provision of a layer of code between
user code, and the OS layer.

At its simplest I'm thinking of something that intercepts file opens/closes/reads 
and writes so that screen output can be redirected into a file, and keyboard
input taken from a file. This is imply implemented by trapping all such calls,
and then (for example) printing or writing the data as appropriate.

A simple shell can then be built that sets up stdin and stdout prior to running
the file. It could also test for files with a specific load/execution address
(say 0000 0000 or ffff ffff) and treat those as scripts.

Programms would need to be writen so they use the new traps (though prehaps
OSWRCH etc could also be interepted).

The ultimate extension of this would be to add relocation info to binaries
so that they could be recursivly loaded (but that could be added later).

Anyone think that this is a good idea?
Is it worth developing (it requires a group commitment to produce software
to run using the new layer)?

Ian