Opening Apple .dmg files on Linux is actually quite easy. I had to open one to try and find a .ppd but I won’t judge you for whatever reason you need to open one for. You’ll need to install a basic tool called dmg2img (http://vu1tur.eu.org/tools/). Use your apt-get or similar tool (I didn’t see it in Fedora’s yum) to install it.
For this example we’ll use Adium. I tried CyberDuck FTP but apparently it just comes zipped up these days.
So you have Adium_1.3.10.dmg all you need to do is this:
owen@linux-blog:~/Downloads$ dmg2img Adium_1.3.10.dmg
and you’ll end up with something like:
dmg2img v1.6.2 is derived from dmg2iso by vu1tur (firstname.lastname@example.org)
Adium_1.3.10.dmg --> Adium_1.3.10.img
reading property list, 20674 bytes from address 22348691 ...
opening partition 0 ... 100.00% ok
opening partition 1 ... 100.00% ok
opening partition 2 ... 100.00% ok
Archive successfully decompressed as Adium_1.3.10.img
You should be able to mount the image [as root] by:
mount -t hfsplus -o loop Adium_1.3.10.img /mnt
The last step you’ll need to do is what it tells you above. Most distributions will automatically modprobe the hfsplus module when you run the mount. Use sudo rather than switching to root and I’d also recommend putting it somewhere that makes more sense than /mnt. Perhaps mkdir /mnt/Adium and mount to there.
sudo mount -t hfsplus -o loop Adium_1.3.10.img /mnt/Adium
Don’t forget once you’ve done it to remove the /mnt/Adium directory!