[tytso]

Actually, that's not quite right. With pretty much all modern Unix systems, the kernel supports process groups, and the control-C gets sent to the tty's foreground process group. Since the shell will set up a new process group when it sets up a new command (or command pipeline) to be run, and then sets it to be the foreground process group, the shell never gets the signal, and isn't involved in forwarding the signal to the job. Instead the tty sends it directly to the command currently attached to the tty.