Newsgroups:	comp.os.msdos.djgpp
From:	"Mark Wodrich" <mwodrich AT ct DOT lia DOT net>
Subject:	Re: Porting real-time, multiprocess, distrib. OS Kernel to djgpp?
Message-ID:	<01bbcc19$46d910a0$22901ac4@mark-s-pc>
Date:	Wed, 06 Nov 1996 19:30:28 GMT
References:	<1996Nov5 DOT 133017 AT uctvms DOT uct DOT ac DOT za> <327FF2E8 DOT 68B4 AT gbrmpa DOT gov DOT au>
Lines:	44
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Leath Muller <leathm AT gbrmpa DOT gov DOT au> wrote in article
<327FF2E8 DOT 68B4 AT gbrmpa DOT gov DOT au>...
> > I have a friend who has developed a real-time, multiprocess, threaded,
> > object-orientated, event-driven kernel.  Currently it runs on the 8086
> > processor, and consists of C++ with Assembly code for the "inner
magic".
> 
> On an 8086? Are you sure?

Yes, I'm sure! ;-)  The system uses the system timer to do task switching,
and provides access to kernel routines through a software interrupt (much
like DOS does).  The code is designed to be portable, ie. not rely on
"fancy" processor modes.  He will be working on a Motorola 68k port as part
of his Masters degree, so it may be easier to tackle the djgpp port once
this has been done.

> object orientated - I don't really get this bit,
By object-orientated, I mean that it transparently supports C++ methods
being invoked in response to an event.  Events are just messages which are
generated by hardware (keyboard,mouse,cards), or processes running on the
machine (or network!).  The kernel checks who is "registered" for an event,
and creates a process for any C++ methods required to run in.

> The fact that this guy wrote this on a 8086 is impressive - how much
> free ram do you have after you run it? ;) 
The kernel sits on top of DOS, and is pretty small (< 64Kb), so you have
around 500Kb left in real-mode DOS.

> > (Oh, the kernel is also distributed, ie. events and processes can be
sent
> > between machines on a network, but this is still in development).
> 
> Sorry, just can't get passed the 8086 bit... Are you SURE it was on an
> 8086???
> Is it just me, or would writing on the 8086 be more hassle than its
> worth...
> 
Once again, as far as I know all this works on an 8086.  Obviously it was
not trivial to implement...  If there is more interest I'll ask the author
to try to explain stuff himself, since I only know second-hand info.

Adios
Mark.

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