read "control d" from the keyboard

im trying to create a main function that prints out some values when the user hits control d.

how do i do that?

thanks!

i should know this, but it's never come up for me...
read the scancodes, then test to see if its a ctrl-d (there are two ctrls).

note: ctrl-d is the end-of-file character for unix machines, so keep it in mind in case you're reading it from a file.