I am in terminal mode on Ubuntu, and I'm running emacs with 2 buffers open, one is a ruby file, and the other is a shell (opened by typing M-x shell ), and when I switch to the shell buffer, I want to run the same command that I ran before. I would normally just hit the up arrow in a terminal window, but in emacs, it simply puts the cursor up one line. Does anyone know of keystroke to run the previous shell command from within an emacs shell?