From owner-freebsd-current Wed Aug 5 19:18:14 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id TAA08175 for freebsd-current-outgoing; Wed, 5 Aug 1998 19:18:14 -0700 (PDT) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from godzilla.zeta.org.au (godzilla.zeta.org.au [203.15.68.22]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id TAA08050 for ; Wed, 5 Aug 1998 19:18:02 -0700 (PDT) (envelope-from reilly@zeta.org.au) Received: from zeta.org.au (d14.syd2.zeta.org.au [203.26.11.14]) by godzilla.zeta.org.au (8.8.7/8.8.7) with ESMTP id MAA10190 for ; Thu, 6 Aug 1998 12:17:45 +1000 Received: (qmail 4321 invoked by uid 1000); 6 Aug 1998 01:29:55 -0000 From: "Andrew Reilly" Message-ID: <19980806112955.A4299@reilly.home> Date: Thu, 6 Aug 1998 11:29:55 +1000 To: Terry Lambert , Tom Cc: current@FreeBSD.ORG Subject: Re: Heads up on LFS References: <199808050751.AAA21008@usr02.primenet.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.91.1i In-Reply-To: <199808050751.AAA21008@usr02.primenet.com>; from Terry Lambert on Wed, Aug 05, 1998 at 07:51:42AM +0000 Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Wed, Aug 05, 1998 at 07:51:42AM +0000, Terry Lambert wrote: > > What is SpinOS? Are you sure it is BSD LFS, or is there own LFS? > > An exokernel OS. > It's written in > Modula 3 (of all things) and incorporates nullfs and lfs from FreeBSD, > as well as CAM. I don't think that "of all things" is particularly fair: their reasoning for the entire viability of the project is that they rely on the strict typing and garbage collection of Modula-3 to prevent user-written kernel extensions from breaking other kernel bits. You couldn't really do it in C or even C++. The same logic is used by the Sun JavaOS folks (Java being Modula-3 in C clothes, that's hardly surprising.) The argument is interesting, but a bit too restrictive to be useful in a general purpose sense, I think. Now if you were prepared to rely on hardware memory /protection/ without using the hardware memory /mapping/, you could probably do the same thing in C or C++ (or assembly language). I believe that this has been tried in some of the Acorn ARM based OS's (RiscOS and the Newton OS.) -- Andrew To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message