How To

by "Cajun" David Richard



This issue we will be looking at the new addition to our Web site, disk images. We have recently
reorganized our Add Ons section - separating the products to individual pages and adding links to
the disk images on the ftp site. If you are not familiar with disk images, then this article is for you.

An Image of a Disk

When I first discovered disk images, I thought they were the coolest thing. Well, I think a lot of things are cool the first time I see them. A disk image is basically a file that is the exact copy of a floppy (or any other disk, it's just that floppy disk images are quite common). Because all floppies are the same size and can hold the same amount of information, the disk images for different floppies will be the same size (this is respective to 800K or 1.4MB floppies).

Disk images can be perceived as similar to what negatives are to photography. With a negative, you can create as many prints of the same picture as you want (hence the photographic reference "image"). Because of this fact, disk images are the handiest thing to have when making many copies of the same disk. You can make disks from these images by using a program like Apple Disk Copy or ShrinkWrap.

All of our products are available on disk from the Arizona Mac Users Group. However, if you have a connection to the Internet, you can download a set of images and create install disks for a game. You can use these disks as a backup, or you can give the disks to a friend who may not have access to the Internet. When he's done, he can pass the disks to another and so on...

RAM Floppies

Over the last year, I have had some people contact me about having trouble with long downloads. Sometimes if you are downloading a large file, the file can become corrupted during the process. This is caused by the fact that there is simply more room for error during a longer download. Also, some people may have a limit to the time they can be online, or maybe a limit to the size of the file they can download. Disk images can be handy in these situations as well.

Because the images are essentially segmented versions of the installers, you can use the images in situation where a large download is troublesome or impossible. However, aside from getting floppies together and creating disks, there is an alternate way of using disk images.

When you pop a floppy into your machine, an entity called the Device Manager says, "Hey, there's a disk here!" The System then reads the disk, gets the icon from the desktop file, and mounts it on your computer. You can then click on the disk, open it, read it, etc.

Well, by using disk images and the ShrinkWrap program, you can mount the floppy in RAM. It appears on your desktop just as any floppy would, and you can do all of the things you can do with floppies with the RAM floppy. However, the information for the disk is kept in RAM, not on a disk in a drive. This makes access much faster.

If you mount all of the install disks on your computer, and then start the install process. It will move as fast as it would if you had downloaded the entire installer - in fact, it should be faster because the information is in RAM, and not on a drive (although access times to hard drives is pretty fast). When you are done, simply eject the disks by dragging them to the trash.

You can find the links to the disk images on a product's respective page in the Add Ons section. They are also found on our ftp site along the following URL:
ftp://ftp.AmbrosiaSW.com/pub/disk_images/

If you have any questions about using these disk images, please drop a note to:
help@AmbrosiaSW.com.