Hybrid CDs on Big Sur

[Sriranga Veeraraghavan]

Hi Andrew,

Thank you very much for your instructions!  They were very helpful!

Once I mounted the Windows partition of my cds using mount_cd9660 as you suggested, I was able to use mkisofs from cdrtools to make an ISO9660 image of that partition.  In case it is useful for someone else in the future, the command I used was:

$ mkisofs -v -J -r -V [VOLNAME] -o [PATH TO ISO IMAGE] [MOUNT POINT]

One small thing I observed was that until I used umount to unmount the Windows partition, diskutil eject wouldn’t let me eject the cd (which is somewhat different from cds that the Finder automounts).

Best,

-ranga

> On Mar 8, 2022, at 20:40, Andrew Udvare <audvare at gmail.com> wrote:
> 
> 
>> On 2022-03-08, at 18:49, Sriranga Veeraraghavan <sriranga at berkeley.edu> wrote:
>> 
>> Hi,
>> 
>> I have some older CDs that appear to be master with a Mac (HFS/HFS+) partition and a Windows (FAT32?) partition.  
>> 
>> Under BigSur (on M1), Finder and DiskUtility only seem to want to mount the Mac partition on these CDs and don’t seem to provide a way to access the Windows partition.
>> 
>> I’ve been able to access the Windows partition by running on Linux running under an emulator, but this is somewhat clunky.
>> 
>> Does anyone know of a way (perhaps through a port in macports) to mount the Windows partition on a hybrid CD?
>> 
>> TIA,
>> 
>> -ranga
>> 
>> 
>> 
> 
> You should be able to use /sbin/mount_cd9660 to mount the area seen by Windows (ISO9660 with Joliet).
> 
> mkdir mount-point
> sudo /sbin/mount_cd9660 -r /dev/... mount-point
> 
> To make an image:
> 
> dd if=/dev/... of=x.raw conv=notrunc bs=2048
> 
> Also try installing cdrtools and using the 'readcd dev=/dev/... -clone f=x.raw' command.
> 
> Both of these may result in a proper image that has the ISO9660 filesystem and the HFS. You should be able to mount the ISO9660 file system with the image with /sbin/mount_cd9660 just the same.