Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catalina)

Anything about Mac emulation that does not belong in the above categories.

Moderators: Cat_7, Ronald P. Regensburg

Post Reply
User avatar
Ronald P. Regensburg
Expert User
Posts: 7821
Joined: Thu Feb 09, 2006 10:24 pm
Location: Amsterdam, Netherlands

Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catalina)

Post by Ronald P. Regensburg »

How to create a disk image file from a HFS CD-ROM in macOS 10.15 (Catalina) and macOS 11 (Big Sur).

This procedure assumes you are logged in as Admin user.

1. Insert the CD-ROM in the CD/DVD drive (I used the Apple USB SuperDrive)
- The CD will not be mounted, wait till the drive settles down

2. Find the volume name
- Open Disk Utility (in Apps/Utilities)
- In the Device and Volumes list at the left, the CD volume is shown greyed
- Select that greyed CD volume
- Now you will see in the bottom-right corner the device name*
- Note that name and close Disk Utility
* In my test the device name was "disk5s1s2", it can be different in your case. In the command below replace disk5s1s2 with the name you found.

3. Create the disk image file
- Open Terminal (in Apps/Utilities)
- Open a bash session by typing at the prompt:

Code: Select all

bash
- Hit Return
- Ignore the message about the default shell now being zsh and about how to update to use zsh.
- At the prompt enter the command below, replacing disk5s1s2 with the device name you found and replacing Disk 1 with the name you want the image file to have:

Code: Select all

sudo dd if=/dev/disk5s1s2 of=~/Desktop/"Disk 1.iso"
- Hit Return
- Enter your password (note that you will see nothing happening while typing your password)
- Hit Return

The disk image is now being created on your desktop. It will take some time. Do not interrupt.
When the process has finished, you will see a message in Terminal window similar to this one:

Code: Select all

348426+0 records in
348426+0 records out
178394112 bytes transferred in 106.781745 secs (1670642 bytes/sec)
- Enter this command to eject the CD:

Code: Select all

drutil tray eject
- Hit Return
The CD will be ejected
- Close Terminal
Last edited by Ronald P. Regensburg on Sat Apr 03, 2021 7:24 pm, edited 3 times in total.
Reason: Edited the instructions with an easier way to open a bash session. (Thanks "cgecastro".)
User avatar
mabam
Master Emulator
Posts: 497
Joined: Wed Apr 10, 2013 9:32 am

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catal

Post by mabam »

Ronald,

As always, your guide is very clear and detailed.

There’s something I’d like to add, however:
As described under https://daoyuan.li/solution-dd-too-slow-on-mac-os-x/ and https://unix.stackexchange.com/question ... 091#189091 it will speed up things when using rdisk instead of disk and setting the block size to a multiple of 2 MB when reading a CD-ROM. That would result in the following amended command:

Code: Select all

sudo dd if=/dev/rdisk5s1s2 of=~/Desktop/"Disk 1.iso" bs=6m
User avatar
Ronald P. Regensburg
Expert User
Posts: 7821
Joined: Thu Feb 09, 2006 10:24 pm
Location: Amsterdam, Netherlands

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catal

Post by Ronald P. Regensburg »

Thanks. But when I try this, the whole process does not take less time:

$ sudo dd if=/dev/disk5s1s2 of=~/Desktop/"Disk 1.iso"
Password:
1333683+0 records in
1333683+0 records out
682845696 bytes transferred in 606.767548 secs (1125383 bytes/sec)

$ sudo dd if=/dev/rdisk5s1s2 of=~/Desktop/"Disk 1.iso" bs=6m
Password:
108+1 records in
108+1 records out
682845696 bytes transferred in 606.794664 secs (1125332 bytes/sec)
User avatar
Cat_7
Expert User
Posts: 6121
Joined: Fri Feb 13, 2004 8:59 am
Location: Sittard, The Netherlands

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catal

Post by Cat_7 »

Hi,

Should that not be "sudo dd if=/dev/disk5" of=~/Desktop/"Disk 1.iso" to copy the whole disk?

Best,
Cat_7
User avatar
Ronald P. Regensburg
Expert User
Posts: 7821
Joined: Thu Feb 09, 2006 10:24 pm
Location: Amsterdam, Netherlands

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catal

Post by Ronald P. Regensburg »

Cat_7 wrote:Should that not be "sudo dd if=/dev/disk5" of=~/Desktop/"Disk 1.iso" to copy the whole disk?
When you do that, you will get a file that BasiliskII cannot read. It is the mountable HFS volume that you want for the image. For the CD-ROM that I used, it is the HFS volume named "MW 01/97" (the Macworld January 1997 disk).

Code: Select all

/dev/disk5 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:        CD_partition_scheme                        *784.9 MB   disk5
   1:     Apple_partition_scheme                         683.5 MB   disk5s1
   2:        Apple_partition_map                         1.0 KB     disk5s1s1
   3:                  Apple_HFS MW 01/97                682.8 MB   disk5s1s2
When Disk Utility (on pre-Catalina macOS) is used to create the image, it is also only that volume that is used for the disk image. To find the ID for that volume one can still use Disk Utility in Catalina. See instruction #3 above.
Last edited by Ronald P. Regensburg on Tue Jun 30, 2020 6:01 pm, edited 2 times in total.
Reason:  
User avatar
mabam
Master Emulator
Posts: 497
Joined: Wed Apr 10, 2013 9:32 am

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catal

Post by mabam »

Ronald P. Regensburg wrote:Thanks. But when I try this, the whole process does not take less time:

$ sudo dd if=/dev/disk5s1s2 of=~/Desktop/"Disk 1.iso"
Password:
1333683+0 records in
1333683+0 records out
682845696 bytes transferred in 606.767548 secs (1125383 bytes/sec)

$ sudo dd if=/dev/rdisk5s1s2 of=~/Desktop/"Disk 1.iso" bs=6m
Password:
108+1 records in
108+1 records out
682845696 bytes transferred in 606.794664 secs (1125332 bytes/sec)
So what is supposed to be faster theoretically, in fact is even a fraction of a second slower practically.

Sorry, should have tried it myself before posting.
User avatar
adespoton
Forum All-Star
Posts: 4208
Joined: Fri Nov 27, 2009 5:11 am
Location: Emaculation.com
Contact:

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catal

Post by adespoton »

So if you read the entire disk, you should save it as a <filename>.bin and create a cuefile with the track sizes as indicated via diskutil.

Then you have a bin/cue pair that should work with the recent bin/cue patches for BII/SheepShaver :) If you don't want to go through all this effort and only need the HFS partition, then you're better off just imaging the HFS partition.
cgecastro
Space Cadet
Posts: 1
Joined: Sat Apr 03, 2021 6:42 pm

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catalina)

Post by cgecastro »

Hello,
Ronald P. Regensburg wrote: Mon Jun 29, 2020 9:01 pm How to create a disk image file from a HFS CD-ROM in macOS 10.15 (Catalina).



1. Make sure your shell is bash (the default shell in Catalina is zsh)
- Open System Preferences > Users & Groups
- Click the lock and enter your password to allow changes
- In the list with users, right-click (or control-click) on the current user (you) and choose Advanced Options...
- In the Advanced Options dialog see the "Login shell" menu
- If it shows "/bin/bash", you can click the Cancel button and close Preferences
- If it shows a different shell, choose "/bin/bash" in the menu (The item "/bin/bash" may not be shown at first sight, it is at the top of the menu.)
- DO NOT CHANGE ANYTHING ELSE!
- Click the OK button
- Close Preferences
- No need to restart

Instead of all this just type "bash" in the terminal and it will load a bash session.
In the end type "exit" to return to zsh
The warning about zsh being the default shell also apears.
Tested on BigSur
User avatar
Ronald P. Regensburg
Expert User
Posts: 7821
Joined: Thu Feb 09, 2006 10:24 pm
Location: Amsterdam, Netherlands

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catalina)

Post by Ronald P. Regensburg »

Ah, yes. Much simpler. I did not know that. I will rewrite the instructions above.
(No need to use "exit" to return to zsh. The next time a Terminal window is opened it is back to the default zsh.)
SILearning
Space Cadet
Posts: 1
Joined: Fri Jun 18, 2021 3:34 pm

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catalina)

Post by SILearning »

I just wanted to mention that I was able to use this method for creating a disk image from a 3.5" floppy. On my Mac running 10.4, plugging in a cheap USB floppy drive with an original Adobe Pagemaker Disk, the disk would not mount - no surprise - just like the CD rom. It showed up as a greyed out "disk2" in disk utility though so I gave it a try. Worked perfectly and I was able to install PM 5.0. Thank you so much for all you do on here!
Last edited by SILearning on Fri Jun 18, 2021 3:40 pm, edited 1 time in total.
brklyn.ellie
Student Driver
Posts: 13
Joined: Thu May 21, 2020 8:34 pm

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catalina)

Post by brklyn.ellie »

Had a couple of questions about the beginning of this process:
Ronald P. Regensburg wrote: Mon Jun 29, 2020 9:01 pm
1. Insert the CD-ROM in the CD/DVD drive (I used the Apple USB SuperDrive)
- The CD will not be mounted, wait till the drive settles down

2. Find the volume name
- Open Disk Utility (in Apps/Utilities)
- In the Device and Volumes list at the left, the CD volume is shown greyed
- Select that greyed CD volume
- Now you will see in the bottom-right corner the device name*
- Note that name and close Disk Utility
* In my test the device name was "disk5s1s2", it can be different in your case. In the command below replace disk5s1s2 with the name you found.
I'm using the download suggested on the original SheepShaver setup forum from this page: http://macintoshgarden.org/apps/macinto ... -doors-mdd - Mac OS 9.0.4. When I downloaded it, it turned into Mac OS 9.0.4.toast.

When I try to open the Mac OS 9.0.4.toast file in Disk Utility it shows up briefly under that same name in the "Disk Images" section but then goes away. So I'm not able to locate any other device name for the disk images.

Please let me know if there's something I'm missing!
User avatar
Cat_7
Expert User
Posts: 6121
Joined: Fri Feb 13, 2004 8:59 am
Location: Sittard, The Netherlands

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catalina)

Post by Cat_7 »

Hi,

What are you trying to achieve with your download?
The post is about creating a disk image from a real cd so it can be used with Basilisk or SheepShaver.
But you are downloading a disk image from the garden site that can already be used with SheepShaver. What you are downloading is the same as the end result of making a disk image from a real cd as described in this post.

Best,
Cat_7
brklyn.ellie
Student Driver
Posts: 13
Joined: Thu May 21, 2020 8:34 pm

Re: Creating an .iso from a HFS CD-ROM in macOS 10.15 (Catalina)

Post by brklyn.ellie »

Hi Cat_7,

Thanks for clearing this up - makes sense as to why I couldn't format it in Disk Utility. I'll take other questions to the appropriate spot.

Ellie
Post Reply