I've been using term-mode for a while now and just recently decided to fix something that has been irking me.

See, term-mode allows you to switch between what is called "line mode" and "char mode". In line mode, emacs treats the shell as a plain buffer, except that pressing "return" will send the current line to the shell for execution. This is really cool! It allows for all sorts of fancy things, because you can treat your shell as a regular emacs buffer. This behavior is essentially the same behavior as in comint-mode, another emacs shell.

The second mode of term-mode is character mode. When in character mode, each key you type is sent directly to the subshell (except for a few). Thus, character mode feels like a traditional terminal emulator like Terminal.app on OS X.

The way you switch between them is with C-c C-j/C-c C-k. One will switch the buffer to character mode, and the other will switch the buffer to line mode.

I can never remember which key does what and where. So, the other day I finally decided to sit down and fix the problem. I came up with this:

(require 'term)

(defun jnm/term-toggle-mode ()
  "Toggles term between line mode and char mode"
  (interactive)
  (if (term-in-line-mode)
      (term-char-mode)
    (term-line-mode)))

(define-key term-mode-map (kbd "C-c C-j") 'jnm/term-toggle-mode)
(define-key term-mode-map (kbd "C-c C-k") 'jnm/term-toggle-mode)

(define-key term-raw-map (kbd "C-c C-j") 'jnm/term-toggle-mode)
(define-key term-raw-map (kbd "C-c C-k") 'jnm/term-toggle-mode)

The idea is that what I actually want is a method to toggle which mode the buffer is in. I can then overwrite the previous bindings with this toggle method, and I won't have to deal with this ever again.

Thus, the command jnm/term-toggle-mode toggles a buffer between character mode and line mode. In order to connect the command, we need to hook it up to the correct keymaps. These maps are term-mode-map, which is active when the buffer is in line mode, and term-raw-map, which is active when the buffer is in character mode. So, I hook it up to both key bindings in both maps, and now I no longer have any problem.

I <3 Emacs.