Disk Copy

A second disk utility contained within Jaguar is Disk Copy.  From its name, especially if you came in from the cold of the PC world, you’d think it would allow you to clone one disk to another. Disk Copy really doesn’t do that.  (The best Mac utility for that purpose is Carbon Copy Cloner from Bombich Software-www.bombich.com/software/ccc.htm.)  Disk Copy allows you to make “images” of folders, volumes, or disks that can be stored, compressed, or used to burn CD’s or DVD’s.    Disk Copy’s output is in the form of “disk images” or .dmg files.  If you’ve ever downloaded a program or software update, then you’ve probably seen these on your desktop.  A .dmg file can be thought of as a single file that represents files, folders, volumes, or disks.  An example of a .dmg file is below.  This one is a folder containing pictures (.tiff files) I used to make up this section of the website.

So, what can you do with this .dmg file?  Well, if you double-click on it you’ll find that OS X will automatically launch Disk Copy and expand and “mount” the disk.  This means it will expand the image into whatever structure it had before being turned into a disk image (i.e., file, folder, disk) and then place it on the desktop for use.  When it does that, it will appear as a “removable disk” icon like so:

 Double-clicking on the disk icon opens it into the folder its started out life as.

Had this been a disk or CD/DVD, it would have mounted as a disk, CD, or DVD.  (Make sure you have enough room on your hard disk to support that!)

So, you can use Disk Copy to store files, folders, disks, and CD’s or DVD’s on your hard drive by making an image of the item, store them in less space by using compression, protect their contents by encrypting them, or use them without actually carting around disks by carting around the images and using them when you want to. 

For instance, say a client lent you a CD you need to copy.  You’re on travel and your iBook only has a CD player in it, not a burner.  Your desktop Mac at work has a burner, but the client wants the CD back before you leave.  You could make an image of the CD using Disk Copy, move that to your desktop Mac when you got home, and then burn that image back to CD.  Voila!  Mission accomplished!

The Utility

 Disk Copy can be found in the Applications/ Utilities folder.  To launch it, simply double-click on its icon.  (Its name is highlighted in blue.)

When it launches, it will take over the Menu Bar and display a small window.

Notice that the instruction on how to use it are in the window…assuming you already have either a disk image you want to use or can open Finder to get to a folder or disk you’d like to image.

Click here to continue with Disk Copy!