Path: utzoo!attcan!uunet!lll-winken!lll-lcc!lll-tis!ames!umd5!brl-adm!brl-smoke!gwyn
From: gwyn@brl-smoke.ARPA (Doug Gwyn )
Newsgroups: comp.sys.apple
Subject: Re: Multitasking GS?  Sure, why not.
Message-ID: <8077@brl-smoke.ARPA>
Date: 12 Jun 88 01:26:29 GMT
References: <8Wf-=Jy00V4McuU0C4@andrew.cmu.edu> <379NETOPRMS@NCSUVM> <23275@bu-cs.BU.EDU>
Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 32

In article <23275@bu-cs.BU.EDU> spike@bu-it.bu.edu (Joe Ilacqua) writes:
>	One of the major short coming in the GS is lack of real memory
>management.  Any program can happily write to any memory at any time.

Whitesmiths' Idris operating system managed quite well on LSI-11s,
which had the same problem.  Sure, a buggy program could crash the
system, but I doubt it would be any worse than current Apple IIGS
standalone software, which frequently crashes my GS.

>Programs can bypass calls to the OS, writing directly to the screen
>and disks, ...

Of course the running applications would have to behave themselves.
The IIGS ToolKit and ProDOS take care of practically everything along
these lines, so there is little excuse for IIGS programs to bypass the
official system interface.

>	What needs do be done first is for to write a compiler.  'C'
>would be the most likely candidate, tho if well writen it could have
>other front ends.  This compiler would produce code in a number of
>models, using the 65816 banks.  The use of banks would make easly
>relocatable, as could be loaded by the OS in to any avaible bank.
>This could be done by having no 'long calls' in the code.  The 65816
>allows you to relocate the stack, so each program could have its own
>stack (C does quite a bit on the stack).  With a run time loader the
>program could also have it's own data space or data/stack space.

Where have you been?  The IIGS loader already relocates while loading,
and it provides sufficient functionality to support multitasking.
There is already a C compiler, which is not terrific but should be
good enough.

Restricting code to fit in one bank is unacceptable.