How do you specify command line arguments in Xcode 4?

I just upgraded to Xcode 4 and can't find much documentation on it yet, since it just went gold master. I need to specify a command line argument for testing my application.

The Xcode 3.2 advice doesn't help since everything got moved around.


Solution 1:

Command line arguments and environment variables can be set up in the Run section of the scheme editor.
Product -> Edit Scheme... -> Run -> Arguments (Copy-Paste from the link given by Jano)

Solution 2:

The shortcut cmd + < works too. (Default shortcut)

On Xcode 7 (updated), XCode 10.1

Shortcut : Shift + cmd + <