How do you get terminal to echo / print all key strokes? Looking to see what the terminal gets when you press keystrokes such as alt+a or whatever.

I remember there was a really simple way to do this with a one line command and without installing any extra software, but I can't seem to find it again. 

Any one know?
Found it 

sed -n l

Really useful for debugging problems with terminal programs that benefit from complex bindings like vim.

Or just use cat or sed