From owner-freebsd-hackers Tue Mar 11 09:09:09 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id JAA19641 for hackers-outgoing; Tue, 11 Mar 1997 09:09:09 -0800 (PST) Received: from phaeton.artisoft.com (phaeton.Artisoft.COM [198.17.250.50]) by freefall.freebsd.org (8.8.5/8.8.5) with SMTP id JAA19634 for ; Tue, 11 Mar 1997 09:09:02 -0800 (PST) Received: (from terry@localhost) by phaeton.artisoft.com (8.6.11/8.6.9) id JAA25415; Tue, 11 Mar 1997 09:58:51 -0700 From: Terry Lambert Message-Id: <199703111658.JAA25415@phaeton.artisoft.com> Subject: Re: pcvt/132 columns To: chuckr@glue.umd.edu (Chuck Robey) Date: Tue, 11 Mar 1997 09:58:50 -0700 (MST) Cc: terry@lambert.org, joerg_wunsch@uriah.heep.sax.de, FreeBSD-hackers@freebsd.org In-Reply-To: from "Chuck Robey" at Mar 10, 97 08:14:20 pm X-Mailer: ELM [version 2.4 PL24] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > > As to your question, it's a non-sequitur... DOS supports .EXE files, > > but BIOS POST does not. You also presume (incorrectly) that DOS is > > an OS. > > Terry, I may not think very highly of DOS, even given the context in > which it was written, but it is an OS, at least I maintain it is. Could > you defend that remark? It is a disk loader and a non-reentrant real mode interrupt handler; I know this is already common knowledge... It does not have these OS features: o Multitasking (an OS which can not multitask is a loader, not an OS) o Resource tracking o Memory (the big one) o Open file handles o Anything not hung off the PSP o Memory protection o System reentrancy (there is a single BIOS call stack for most BIOS calls, which is why they are not available to TSR's that don't supply their own system stack) o Fault recovery (pretty obvious it can't be done without resource tracking and memory protection, etc.) In addition, an OS enables software engineering. I could go on for days about how DOS fails in this regard. Regards, Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.