Mac OS X Tip: How to kill the “application downloaded from the internet” dialog box

Look familiar: “XYZ is an application downloaded from the internet. Are you sure you want to open it?” You have two options to put this message to rest. Fnixrom a terminal:

Specify an application:

xattr -d -r com.apple.quarantine /path/app

For example:

xattr -d -r com.apple.quarantine ~/Downloads/SomeApp

or even more useful, specify a folder:

xattr -d -r com.apple.quarantine ~/Downloads

The other choice is to use the Mac defaults command to change the system setting:

defaults write com.apple.LaunchServices LSQuarantine -bool NO