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Difference between .dmg and .app

Maneesh Godbole
Saloon Keeper

Joined: Jul 26, 2007
Posts: 10734

Someone was mentioning about turning a jar into an app in another thread and that caused a bit of a confusion for me.

I noticed that when I download some "installable" it is named .dmg and when I execute the application it, it is an .app file. Would I be correct in thinking this similar to .msi and .exe on windoze?

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Ulf Dittmer

Joined: Mar 22, 2005
Posts: 42956
.app is like .exe, but .dmg is a disk image, not an installer. If you double-click a disk image it will be mounted on the desktop like any other readable device. There may be an option to have an application (possibly an installer) run automatically upon mounting a disk image, but that's not the norm.
Maneesh Godbole
Saloon Keeper

Joined: Jul 26, 2007
Posts: 10734

Oh ok. Got it now.
Hussein Baghdadi
clojure forum advocate

Joined: Nov 08, 2003
Posts: 3479

Why there is DMG in the first place? what is the purpose of treating a software as a device?
Bear Bibeault
Author and ninkuma

Joined: Jan 10, 2002
Posts: 63062

Think of a zip file that acts like a mountable volume.

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