I'd like to assign some shortcut in MAC OS X. But I want to limit to Left Alt only. When I'm assigning it now, both alts do work.
How do I limit it for one side only?
You can use KeyRemap4MacBook to assign them to some unused key combinations first:
<autogen>__KeyToKey__ KeyCode::A, ModifierFlag::OPTION_L | ModifierFlag::NONE, KeyCode::F19, ModifierFlag::COMMAND_L</autogen>
| ModifierFlag::NONE ⌃⌥A would also be changed to ⌃⌘F19.