Feel like playing with DR-DOS in VirtualBox? Have a few virtual hard disk images!

[liam_on_linux]

My occasional project to resurrect DR-DOS and make something vaguely useful from it continues, and in the spirit of "release early, release often", I thought that someone somewhere might enjoy having a look at some of my work-in-progress snapshots.

So while there is nothing vastly new here, building a bootable DOS VM is not completely trivial without what is now some very old knowledge, so I thought these might help someone.

The story so far...

In the OpenDOS Enhancement Project, Udo Kuhnt took Caldera's FOSS release of DR-DOS 7.01 (which they had renamed OpenDOS) and added in FAT32 support and some other things. Caldera spin-off Lineo (later DeviceLogics) implemented these in later, closed-source versions of DOS, but they were not officially FOSS. They also used bits of FreeDOS and were later withdrawn. DeviceLogics has since gone out of business.

Udo's disk images are on Archive.org but they aren't bootable. I've made bootable images you can download. I have a bootable VM of DR-DOS 7.01-08 but I need to clean it up and give it some spit and polish. I also added back the ViewMax GUI from DR-DOS 6.

Meantime, what I have uploaded here are three Zip-compressed VirtualBox VDI files. A VDI is the hard disk of a VirtualBox VM. These contain FAT16 hard disks.

• DR-DOS 6 with ViewMax;


• DR-DOS 7.01 with ViewMax added back in from the above & very basic memory optimisation;


• The later withdrawn DR-DOS 8.

The quick way to use them:

1. Download the image.


2. Run VirtualBox. Create a new VM. Call it (e.g.) "DR-DOS 6". You must have "DOS" in the name for Virtualbox to correctly configure the new VM for DOS! Otherwise you must manually do that part.


3. When you get to the "create or add hard disk stage", stop!


4. Switch to the file manager. Unzip the file. Put it in the newly-created VM's directory.


5. Go back to VirtualBox. Pick "add an existing hard disk". Browse to the file you just moved into place. Click it, and click "Add".


6. Now you're back at the "choose a disk" dialog. Pick the newly-added one.


7. Finish VM setup.

Now you can start the new DOS VM and enjoy.

Comments

[killap]

Hi Liam! I first wanted to thank you for all the work you did around this. I have been using your floppy disk images from the other blog thread for the past few months and things have been great. It's been very nostalgic running DOS again and playing through games/demos of my childhood. It really is great to see people working on projects like this well past the prime DOS days.

I am curious what progress you ever made around bootable DOS USB keys that you mentioned on the other blog. That would make testing on some machines I'm building much easier. :)

I'm also curious if you ever created a single full DR-DOS 7.01-08 floppy image, so that it wasn't necessary to start with 7.01 and then copy your files over. Did that happen?

Separately here you mention a VM of 7.01-8. Was that ever polished and released? If a full _floppy_ image existed though, that would make my day and actually be more useful to me. :)

Anyway, thank you again for everything. This really helped me get DR-DOS up and running with the further improvements made by Udo.

[liam_on_linux]

Oh, that is great to hear!

I have been intermittently experimenting since, but I don't have as much time as I used to. Less than 6 months after this post, I got a new and much more demanding job. It leaves me tired and less given to hacking.

In that other post, for clarity, when I label v 7.01-08 as "work in progress", it was Udo's WIP, not mine! What I meant to indicate is that this is his unfinished version. For me, it is as good as I can make it, but I did encounter problems with it.

I have not worked on floppy installation images, no.

The updated VM images are here. The boot floppies are in this post: https://liam-on-linux.livejournal.com/58013.html

Does that help?

[killap]

I hear that about demanding job, leaving less energy for hacking/coding hobbies. Don't burn yourself out. :)

Sorry, yes, I didn't mean to take credit away from Udo when I had said "copying over your files". Credit to all of you, for sure.

Understood about further work on floppy installations.

Just so that it's clear for me, if I want to make a complete OS using Udo's last work (7.01-8), do I need to just install DR-DOS 7.01 (from like WinWorldPC), boot only your -8 floppy image and copy the files over from it to the full DR-DOS that was just installed? I wasn't sure if things were not cumulative and I also needed files from prior version boot floppies you put together (-6, -7). Not all the same files are in each floppy image, which is why I am asking. For example, the 7.01-8 floppy doesn't have SHARE.EXE, SYS.COM, TASKMGR.EXE, XCOPY.EXE like is in the 7.01-7 floppy. And then -6 has IBMDOS|BIO.COM but the later ones have DRBIO|DOS.SYS.

I did end up copying the set of files from each floppy over separately for my install, which has been working fine, but just hoping to get clarity on the cleanest, proper method.

Thanks!!

[liam_on_linux]

Absolutely no problem about credit or anything. It's all his work. All I did is a few commands to make boot disks. :-)

It is a couple of years ago now, and I'd forgotten that there were some differences in there. I will try to update these images when I can!

So, in the meantime, copy the files from one, then the next, then the next. That will update the released 7.0.1 to the latest.

But, to re-iterate:

I had some problems with the last-ever WIP build. Some stuff did not seem to work right in testing in VirtualBox and I haven't had time to test again in VBox 7.x.

So for my own use, I avoided 7.0.1-08 and I was using the previous version.

I wish some company would come along, buy up the IP and update this. :-(

I can see 2 potential opportunities here:

[1] A 21st century Amstrad PCW: a modern DOS word-processor on a USB key. WordPerfect is still around and still current. Corel could buy DR-DOS and release the last ever DOS WordPerfect, 6.2, on a bootable USB key, as a distraction-free writing tool.

Snag: DOS can't boot on any UEFI PC.

[2] Multiuser DOS is a true native 32-bit PC OS. It is probably easier to make Multiuser DOS run on UEFI, and offer that as the modern successor version.

One of the things that killed Multiuser DOS in the old days is that it wasn't compatible with DOS device drivers. So, you could not easily use it with sound card, SCSI cards, DOS network stacks, etc.

But they are all gone now anyway. So that is much less of a problem. Most people don't want or need to network DOS in the 21st century.

Now, Multiuser DOS is just a multitasking 32-bit DOS. So long as it can boot off USB and run DOS apps, that's all most DOS users would want or need.

I have written about that more recently for my day-job:

https://www.theregister.com/2022/08/04/the_many_derivatives_of_cpm/