How to bind CTRL-<home> and CTRL-<end> to beginning/end-of-buffer in Emacs?

Question

Using PuTTY to connect to Linux from Windows and running Emacs: How do I bind CTRL-<home> and CTRL-<end> to beginning-of-buffer and end-of-buffer respectively?

I've been searching the web for a while on this one. I've seen various suggestions but none of them seem to work. I understand that PuTTY can be configured to send different character codes for the HOME and END keys based on a setting and I can see what those codes are in the bash shell (via C-v ) and in Emacs (via C-q). I've read that I might need to "bind" those codes someone in my .bash_profile file and/or I then might need map those codes via a keymap in my .emacs file.

Ultimately I want to be able to add something like this to my .emacs file ...

(global-set-key (kbd "C-<home>") 'beginning-of-buffer)
(global-set-key (kbd "C-<end>") 'end-of-buffer)

... and make CTRL-<home> and CTRL-<end> behave as they do in most native Windows text editors.

Has anybody been able to make this work? Please share your wisdom.

Answer 1

Although this question being about Putty makes the actual issue off topic, the question is applicable (since troubleshooting is required to identify the cause).

As a possible solution with Putty:

set PuTTY > Terminal > Features > Disable Application cursor keys mode to checked

Source Using ctrl-arrow keys with putty and screen

I cannot guarantee that it will resolve all the issues but it appeared to be enough to allow CTRL+arrow to send the correct escape codes.

Answer 2

It turns out that this is a PuTTY issue as opposed to an Emacs issue, so I apologize for abusing the Emacs forum. Since the frustration started with trying to configure Emacs though I'm guessing that others may run in to the issue too and so I'll post my own answer to hopefully provide those poor souls with some solace.

It seems that PuTTY does not send any keyboard codes for CTRL combinations with certain keys (including [home] and [end]). So, when using PuTTY the CTRL-[home] that I enter on the keyboard doesn't even get to bash or Emacs and so there's no way to bind that to anything. This is unfortunate.

Other terminal software may do this though. I know now that my xterm (I'm using Cygwin with XFree86 from Windows) does. So when using xterm, and launching character mode Emacs from there (emacs -nw), I can get the behavior I want. I have also realized that I can get that behavior if I use an XServer and launch the X version Emacs from PuTTY (emacs) too. So I don't have to completely abandon PuTTY.

Well, at least I learnt something today. I hope this answer helps someone else one day.

Here's the relevant section of my .emacs file ...

;; Notes:
;; * PuTTY doesn't send control characters for CTRL-<home> or CTRL-<end> so there's
;;   no way to make those key combinations work in character mode Emacs launched from
;;   a PuTTY terminal.  Character mode Emacs will work if launched from an xterm
;;   though and X mode Emacs launched from PuTTY will work too.
;; * Also, PuTTY mis-maps the <end> key to <select>

;; Make CTRL-<home>/<end> work like in Windows.
;; X mode Emacs or character mode Emacs launched from xterm only.
(global-set-key (kbd "C-<home>") 'beginning-of-buffer)
(global-set-key (kbd "C-<end>") 'end-of-buffer)     ;; Works in X, not in PuTTY 
(global-set-key (kbd "C-<select>") 'end-of-buffer)  ;; For PuTTY

;; Make <home>/<end> work like in Windows
(global-set-key (kbd "<home>") 'beginning-of-line)
(global-set-key (kbd "<end>") 'end-of-line)         ;; Works in X, not in PuTTY
(global-set-key (kbd "<select>") 'end-of-line)      ;; For PuTTY