Mounting Old Windows/Mac Hybrid CDs on Mac OS X
For the impatient, here’s the solution that worked for me:
mkdir ~/cdrom
sudo mount -t cd9660 /dev/disk2s1 ~/cdromI found an old CD from 2002 that had some files that I wanted to view. I was hopeful that when I inserted the disk that the drive would mount and the files would show up in Finder. Unfortunately, it wasn’t that simple.
The drive accepted the old CD, and I could hear some activity, but nothing showed up in Finder. The first thing I did was bring up the Disk Utility to see if the device was recognized at all.
Disk Utility clearly recognized that a CD had been inserted, and even was able to read the partitions. In spite of that, it wasn’t automatically mounting the CD.
According the Disk Utility, the Device was disk2, so I tried to mount /dev/disk2. I had to specify the filesystem type, so I took a guess that it was msdos.
sudo mount -t msdos /dev/disk2 ~/cdrommount_msdos: Unsupported sector size (0)
mount: /Users/malmer/cdrom failed with 71
My next step was to wander around the internet looking for solutions.
One webpage recommended that I see if Mac understood what filesystem was on the CD.
file -s /dev/disk2/dev/disk2: data
That wasn’t informative. I took at look at the various versions of mount to see if there were any other likely candidates.
ls /sbin/mount*/sbin/mount /sbin/mount_cddafs /sbin/mount_msdos
/sbin/mount_9p /sbin/mount_devfs /sbin/mount_nfs
/sbin/mount_acfs /sbin/mount_exfat /sbin/mount_ntfs
/sbin/mount_afp /sbin/mount_fdesc /sbin/mount_smbfs
/sbin/mount_apfs /sbin/mount_ftp /sbin/mount_udf
/sbin/mount_cd9660 /sbin/mount_hfs /sbin/mount_webdav
I tried exfat, because that’s another old Windows filesystem.
sudo mount -t exfat /dev/disk2 ~/cdrommount_exfat: /dev/disk2 on /Users/malmer/cdrom: Permission denied
I then searched the web for what formats were likely used for CDs from that era. ISO9660 and UDF were both candidates.
sudo mount -t cd9660 /dev/disk2 ~/cdrommount_cd9660: Invalid argument
mount: /Users/malmer/cdrom failed with 1sudo mount -t udf /dev/disk2 ~/cdrommount_udf: /dev/disk2 on /Users/malmer/cdrom: Device not configured
mount: /Users/malmer/cdrom failed with 1
At this point, it finally occurred to me that maybe /dev/disk2 wasn’t exactly the right device.
ls /dev/disk2*/dev/disk2 /dev/disk2s1 /dev/disk2s1s1 /dev/disk2s1s2
If I’d looked a little more closely at the Disk Utility, I would have seen that in addition to disk2, it also mentioned disk2s1.
I tried mounting /dev/disk2s1, and that’s what did the trick.
sudo mount -t cd9660 /dev/disk2s1 ~/cdromI was able to copy the files. I then unmounted the CD.
sudo umount /dev/disk2s1My final problem was that I wasn’t able to eject the CD. It didn’t show up in Finder. When I tried to eject it in Disk Utility, I got the message Failed to eject [disk name] because it is currently in use. I tried drutil tray eject, and it returned without doing anything. In order to eject the CD, I had to reboot my machine.
It’s not often that you need to read files from an old CD, but hopefully this will save somebody some time and frustration.
