Is it possible to launch a program in a specific language?

Solution 1:

There is a freeware, Language Switcher, to launch a single application with a different languages.

it's really simple and work amazingly.

You can change the language inside the preferences file of the application :

defaults write com.apple.TextEdit AppleLanguages '("en-US")'

Or just run once one application with another language :

/Applications/iCal.app/Contents/MacOS/iCal -AppleLanguages '(de)'

To determine the bundle identifier, run

mdls -name kMDItemCFBundleIdentifier /Applications/Mail.app

or directly in one command:

defaults write $(mdls -name kMDItemCFBundleIdentifier -raw /Applications/Mail.app) AppleLanguages '("en-UK")'

(via SuperUser)