dmg2img software package provides Tool for converting compress dmg files to hfsplus images, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install dmg2img
dmg2img is installed in your system.
Make ensure the dmg2img package were installed using the commands given below,
$ sudo dpkg-query -l | grep dmg2img *
You will get with dmg2img package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | Utilities |
| Package | dmg2img |
| Version | 1.6.5-1 |
| Description | Tool for converting compress dmg files to hfsplus images |
| Sub Section | Utils |