Not a big fan of keeping old CDs around

January 24, 2011 6:34 AM

Classic Mac emulation-filter: I have apps that require CDs to run. How can I convert my CDs to mountable disk images in SheepShaver/OS 9?

I'm running SheepShaver on OS X. I can use the CD-ROM driver so the virtual machine sees discs inserted in the physical computer but I'm trying to avoid that by running everything off the HDD. Should I make the disk images in OS X or OS 9? What app should I use to make them, and what format should they be? Are there caveats I should be aware of, where apps won't recognize the disk if it's not actually a CD? If so, is there a setting in SheepShaver to get around that?

posted by The Winsome Parker Lewis to computers & internet (15 answers total)

First step should be making the image in the Disk Utility app that comes with your Mac, it's pretty simple and you can try it straight away.

Applications > Utilities > Disk Utility

I haven't got a CD to hand, but I think you either right click the CD in the left hand column, or go to File > New > New Disk Image from [CD]

You can then mount the 'CD' by double clicking the .dmg file. For all intents and purposes, that is now a proper volume that should be indistinguishable from the original CD. Give it a go.
posted by derbs at 6:58 AM on January 24, 2011

You're talking about in OS X, right? I don't believe .dmg files are mountable in OS 9.
posted by The Winsome Parker Lewis at 6:59 AM on January 24, 2011

Forgot to say - this is in OS X. I think you can add the volumes in the Sheepshaver preferences. If not, then it's time to try the OS9 approach.
posted by derbs at 7:01 AM on January 24, 2011

I'm sure there was a disk utility in OS9 as well. I think they made .img instead of .dmg files - but i'm not 100% about that
posted by derbs at 7:11 AM on January 24, 2011

OS 9 has Disk Copy, which if I remember correctly is the nearest analog to OS X's Disk Utility, for both making and mounting disk images.
posted by Blazecock Pileon at 7:14 AM on January 24, 2011

A ha. Disk Utility was called Disk Copy in OS9. Should be in the Utilities folder on the root of your system hard disk. Go to the Images menu > Create image from disk...

Screenshot here
posted by derbs at 7:16 AM on January 24, 2011

I don't have the machine in front of me right now but I'll try it later tonight. Disk Copy sounds ideal since it's within the emulated environment. I seem to recall trying this many years ago (on a real OS 9 system) and having trouble getting apps to treat the disk image as a real CD. I could be misremembering. Are there any obvious gotchas I should be aware of going into this?
posted by The Winsome Parker Lewis at 7:27 AM on January 24, 2011

The way derbs is recommending is probably going to be better, because the mounted volumes will be indistinguishable from a real CD to OS 9, by having the emulator handle it and present it as such. At least on OS X, some games check to make sure there is a physical CD inserted, and won't run if the data is just on what it can tell is a mounted disk image.
posted by floam at 7:47 AM on January 24, 2011

I used to make disk images of Civilization and Railroad Tycoon discs, so that I could play these games on the road without dragging physical media with me. The games used the mounted discs as a kind of copy protection dongle. Worked fine, as far as I can remember.
posted by Blazecock Pileon at 7:47 AM on January 24, 2011

(Note, I've never actually used SheepShaver. I'm assuming it has some facility to fake a CD drive in that manner.)
posted by floam at 7:49 AM on January 24, 2011

SheepShaver maps the physical CD drive to the emulated computer. I can put the CDs in and OS 9 will see them. It's fairly limited though, as it doesn't recognize when I eject or insert a disc; I have to boot the virtual machine after putting the disc in, or it won't see it. Which requires a virtual reboot whenever I want to change discs (part of the reason I'm looking to switch to images instead of real CDs).

Thanks for all the help, I'll be trying Disk Copy when I get home.
posted by The Winsome Parker Lewis at 8:17 AM on January 24, 2011

Going on derbs' and floam's advice, you can mount the .dmg in SheepShaver so it shows up as an actual CD to OS 9. This should avoid any problems of the mounted disk not actually appearing as a CD-ROM.

In SheepShaver VM settings, in the Setup tab, under Volumes press the Add button, then open the .dmg. Make sure "Disable CD-ROM driver" is unchecked.
posted by zsazsa at 9:16 AM on January 24, 2011

I set up a system under Mac OS 9 many years ago where I converted all the kids' games into Disk Copy disk images. As I recall all of them worked fine. The OS 9 Disk Copy mechanism had a provision for the equivalent of AutoRun under Windows; you could set up the disk image such that when you mounted it such-and-such application would start up automatically, so all those CD images were simple double-click-and-start-BlahApp-automatically. I think i wrapped the whole thing in an AppleScript that watched for the target app to quit and then dismounted the image.

Memail me if you want me to see if I can dig up a prototype of this system.
posted by chazlarson at 9:20 AM on January 24, 2011

In the few occasions where Disk Copy couldn't make a mountable .dmg in place of the physical disk, I used ShrinkWrap to make a .img of the disc(s) in question. And only a very few CD-based games wouldn't work with this method. MeMail me and I'll send you the latest copy of ShrinkWrap I have in my archives.
posted by mrbarrett.com at 1:34 PM on January 24, 2011

Little slow on the reply here, but now that it's the weekend again I finally got some time to experiment.

Disk Copy would not successfully create an image but kept giving me the error "the image disk operation did not complete (-50)". So instead, I did it in Disk Utility under OS X. First I tried making a read-only .dmg file, but OS 9 couldn't read it: it saw the volume, but wanted to format it.

So I saved the image as a "DVD/CD master" file, which has the .cdr extension. I've never used that format before. Then I moved the image into the SheepShaver folder for safe keeping.

In the Volumes tab of the SheepShaver GUI, I was able to add the .cdr image as a volume to mount when I boot the virtual machine. I started it up, and voila! The icon showed up on the OS 9 desktop, just as if I'd inserted the physical CD. I tested it by opening the app it depends on, and it works beautifully. Looks like my issue's solved. Thanks, everyone!
posted by The Winsome Parker Lewis at 12:28 PM on January 29, 2011