Fixing your mac keyboard in X11 (RHEL 7)

Alternatively: How xkb works, and how to change keys which are wrong. On OS X, there is no alt+gr. Combinations of shift and alt are used instead. Both alt keys behave the same. You can make your Apple internal or external keyboard behave like this on Linux. This blog post shows how, but please note that it changes the behavior of your alt keys. So keyboard shortcuts which rely on alt might not work any more. Read more