Search code examples
macoszipdmg

.dmg that expands like a .zip

I swear that I've seen Mac OS X applications distributed as .dmg's that, when opened, expand and leave the application in place (deleting the .dmg) instead of mounting a virtual disk.

How are these auto-expanding .dmg archives created?

Solution

  • This is called an "internet-enabled" disk image. It's basically a normal disk image, but with a special setting that says it should be expanded rather than mounted. You can create one by making a standard disk image, then running:

    hdiutil internet-enable /path/to/image.dmg

    You can reverse this with:

    hdiutil internet-enable -no /path/to/image.dmg

    See the hdiutil man page for more info. Also, this page has an AppleScript to automate the process.