Message-ID: <38440078.E9981F7D@maths.unine.ch> Date: Tue, 30 Nov 1999 17:51:07 +0100 From: Gautier Organization: Universite de =?iso-8859-1?Q?Neuch=E2tel?= X-Mailer: Mozilla 4.51 (Macintosh; I; PPC) X-Accept-Language: en MIME-Version: 1.0 Newsgroups: comp.os.msdos.apps,comp.os.msdos.djgpp,comp.os.msdos.misc,comp.os.msdos.desqview Subject: Re: Multitasker for DOS References: <81v5nc$d7f$1 AT nnrp1 DOT deja DOT com> <3843AAA4 DOT 7A042288 AT maths DOT unine DOT ch> <820p8n$hbn$1 AT nnrp1 DOT deja DOT com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit NNTP-Posting-Host: mac13-23.unine.ch Lines: 38 To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Reply-To: djgpp AT delorie DOT com > I don't think there's something principally new to be done about > DOS, at least as I see it. My system currently runs on top of DOS and > is not bound to any specific vendor or version. It takes like 200 K of > memory and doesn't impose further system requirements. > The most significant difference probably is that I'm still flexible. > I'm not sure by now that I want to develop a whole DOS package. I can > customize a multitasking solution to a legacy DOS-based system or > custom DOS-based embedded system rather than pull you to use something > given and unchangeable. Interesting. You may see how the kernel in Lineo's EMM386 behaves - especially for making the mouse interrupt live under each task when it has been set before launching multi-tasking mode, concurrency along with the built-in DPMI server (works!). Their API documentation may be an inspiration too (if still online...). Converging to a thing that works on more than 1 machine may be non-trivial... How to share resources can be a challenge, too: DR-DOS shares a RAM-disk (and other disks), MS-Smartdrive cache, but (hopefully) the mouse cursors are independent on each task, as well as graphics modes, screen memory etc. I suspect there is a lot of subtle choices to do (the IRQs, the network resources). The DR-DOS multitasking kernel is also helped by structures prepared in the real-mode machine (IBMDOS / IBMBIO / COMMAND) for a switching to a multitasking mode. Look for instances of the word `multitasking' in the sources of DR-DOS real-mode kernel. It can help seeing how to implement things in a vendor-independent way. Anyway, good luck and there will surely be plenty of alpha testers on these NG... -- Gautier _____\\________________\_______\ http://members.xoom.com/gdemont/