Disk Images, DiskCopy, and ShrinkWrap

Years ago, Apple had a problem. It wanted to distribute software via the
Internet. But some of the software it wanted to distribute, such as its
PlainTalk Speech kit, wasn’t just a single control panel; it was a suite of files
— extensions, control panels, and so on — that had to be placed into the right
spots in your System folder. To ensure that all these pieces would go into the
right places, Apple also needed an Installer program. How on earth could
Apple distribute all of these pieces electronically — while still keeping them
together, with an installer, in an arrangement the installer understood?

The solution: Apple created disk images. A disk image (a file whose name
generally ends with the suffix .img) is an increasingly common file format for
downloaded software, especially from Apple. But once you’ve downloaded an
.img file to your hard drive, you can’t do a thing with it — unless you have a
program that can open it.

In this case, the program you need is DiskDup + (shareware), Disk Copy or
Disk Image Mounter (from Apple, available from its Web site) — or the much
superior ShrinkWrap (from Aladdin, and included with this book).

Here’s how you work ShrinkWrap: Whenever you encounter an
.img file — including the Disk Tools floppy-disk “images” that come on the Mac OS 8.5
CD-ROMs — double-click it (if you have Disk Copy) or drag it onto
ShrinkWrap’s icon. That’s it; a “virtual floppy-disk” icon appears on your
screen, exactly as though it’s a real floppy disk (the lower-right icon in Figure
22-7). Double-click it to see what Apple has in store for you — an installer, a
Disk Tools floppy’s contents, or whatever. When you’re finished using the
mounted disk image, drag its icon (not the original .img file!) to the Trash

You can also create a disk image. Why would you want to do so? Maybe you,
like Apple, want to distribute something (a little presentation, for example)
to friends, confident that all pieces will remain in their original folder
configurations. Maybe you haven’t switched to the HFS Plus hard drive-
formatting scheme (see Chapter , and you realize that a lot of small files
won’t waste their usual 64K apiece if they’re all stored together on a much
smaller “virtual disk.” (That last sentence will make a lot more sense once
you’ve read Chapter 8.)
Anyway, to create a disk image of your own, just drag a disk or folder onto
ShrinkWrap’s icon. The new .img file is created automatically. (You’re not
limited to creating disk images of floppies, by the way. ShrinkWrap is perfectly
happy to create disk images of entire hard drives, Zip disks, Jaz cartridges, or
whatever; it even offers to compress the contents in the process. As thousands
of teenage software pirates have discovered, that feature makes ShrinkWrap
ideal for creating easily uploaded duplicates of entire CD-ROMs.) LOL!

No ShrinkWrap needed — and passwords
ShrinkWrap’s Preferences are worth checking out. Among our favorite features,
for example, is a self-mounting option. It lets you create disk-image files that your friends can open even
 if they don’t have Disk Copy, ShrinkWrap, or a similar
program. A self-mounting disk image is just as user-friendly as, say, a self-
extracting archive, as described earlier in this chapter — just double-click to
mount the “virtual disk” on the screen.

Another great preference: You can opt to protect an archive with a password.
Yes, all you Mac fans who’ve e-mailed us with this question — now you can
protect specific folders on your hard drive from prying eyes. (Remember the
password, though. There’s no “back door” to ShrinkWrap.

--- http://macos9lives.com/downloads/manuals/MacOs/Mac%20Secrets%205th%20Edit.pdf

"As thousands of teenage software pirates have discovered, that feature makes ShrinkWrap
ideal for creating easily uploaded duplicates of entire CD-ROMs "

^^ yet here we are using .toast images as a standard instead of .img..
when .img is native to both X + 9... and Toast. well.. requires Toast!!
maybe it would have been more convenient for all,
if we were all using diskcopy or skrinkwrap from the start!