Mac OS from scratch, on MAME 0.232+ (or a recent Git pull). (post 1/2)
Prereqs: the Apple Legacy Recovery CD-ROM, which you can get from Macintosh Garden
. WARNING: Internet Archive has a version of the CD which does not work properly - it boots, but the file association with the .scr scripts doesn't work.
First, create a hard disk image. I'll give instructions for one that's around 500 MB, but you can go up to at least 1 GB without MacOS getting upset.
For an uncompressed CHD, enter chdman createhd -c none -chs 1023,63,16 -o myhdd.chd
. If you're on Linux, BSD, or modern macOS, you can easily create a non-CHD raw image with dd if=/dev/zero of=myhdd.hdv bs=1000000 count=500
Second, start MAME with the hard disk image you just created and the Legacy Recovery CD-ROM mounted on the Mac IIci driver: mame maciici -ramsize 8M -hard1 myhdd.chd -cdrom "Apple Legacy Recovery Oct 1999.iso"
(use myhdd.hdv instead if you chose that route to create the image).
The system will start up and you'll see a Finder desktop like this:
Double-click the "Legacy Recovery" icon:
And then double-click "Disk Utilities" and then "Formatting Software":
Next double-click "Drive Setup 1.5":
Click your hard disk image, which will show as "<not initialized>" and then click the "Initialize.." button:
When this warning comes up, you can pick "Custom Setup..." if you know what you're doing and want to partition the hard disk in some special way, or just click "Initialize" to get a single partition the full size of the disk:
You should get this success: