I know for most people using mkisofs is second nature, but I needed to get a machine running MS-DOS without floppies… and it had to be on the bare metal.. Oh joy.

Now I’ve kind of done this before but I’ve never gotten it to preserve the directory structure.  It seems that it’s important to specify some output…

The ‘fun’ thing is that I was able to use virtual pc to build the boot diskette with IDE cdrom drivers, and make sure it works in that it mounted the CD and set the path there…

So I have extracted my MS-DOS install from the floppies into a directory on my pc and I keep the file dos622_1.img in the same directory so mkisofs can place it in the image.  Then it’s just a matter of running:

..\mkisofs.exe -o ..\x.iso -J -r -v -V test_disk -b dos622_1.img .

And I get an x.iso that can boot MS-DOS, and has all the dos commands in place, I can partition & format the hard disk and copy DOS into place.

It’s not much to see, but if you need legacy stuff it’ll be a life saver.. and I know I’ll end up losing the flags and needing them again!