Alfred for OS X is able to capture the keyboard presses Alt+Space, which it uses as a "Toggle Alfred" command. It captures this even when it is not the active/key window. This question about "detecting system-wide keyDown events" tells me that there are multiple methods for achieving this, but all require "assistive device" access. Alfred does not appear to have this access, so it must be using a different method.
How does Alfred achieve this? What API is it using?
