🚀 go-pugleaf

This is the code I use to get the ESCape key (F11) working on my DEC vt220
(VT200 mode). In this mode the ESC key sends the sequence "[23~".

I hope you can find some ideas to put in the future releases of GNU
Emacs. (I'm not sure I didn't send this code to GNU a couple of years
ago. In any case .....)

************* /usr/local/lib/emacs/lisp/default.el ********************
;;;
;;; The following has been added to have a nice behavior under
;;; incremental search with the long escape sequence sent by the
;;; ESC (F11) key
;;;
;;; S. Diomedi - TECSIEL SpA
;;;

(if (or (string-equal (setq default-term (getenv "TERM")) "vt200")
	     (string-equal default-term "vt220"))

    (progn
      (if term-setup-hook
	  (progn 
	    (setq user-term-setup-hook term-setup-hook)

	    (fset 'vt200-ESC-term-setup-hook
		  '(lambda ()
		     (if (boundp 'CSI-map)
			 (progn
			   (setq ESC-pf
				 (where-is-internal 'ESC-prefix CSI-map t))
			   (setq ESC-pf-length (length ESC-pf))))
		     (funcall user-term-setup-hook)))
	    )

	(fset 'vt200-ESC-term-setup-hook
	      '(lambda ()
		 (if (boundp 'CSI-map)
		     (progn
		       (setq ESC-pf
			     (where-is-internal 'ESC-prefix CSI-map t))
		       (setq ESC-pf-length (length ESC-pf))))
		 (setq ESC-pf-length (length ESC-pf)))))

      (setq term-setup-hook 'vt200-ESC-term-setup-hook)))


************* /usr/local/lib/emacs/lisp/isearch.el ********************

....

*** isearch.el	Tue Jun 18 16:52:40 1991
--- isearch.el.org	Wed Jan  9 23:01:00 1991
***************
*** 113,143 ****
  		  (setq unread-command-char char)
  		  (throw 'search-done t))
  		 ((eq char search-exit-char)
- ;;;
- ;;; The following has been added to have a nice behavior under
- ;;; incremental search with the long escape sequence sent by the
- ;;; ESC (F11) key
- ;;;
- ;;; S. Diomedi - TECSIEL SpA
- ;;;
- 		  (if (and (boundp 'ESC-pf) ESC-pf)
- 		      (if (eq (setq char (read-char)) 91)
- 			  (let ((index 0))
- 			    (while (< index ESC-pf-length)
- 			      (if (eq (setq char (read-char))
- 				      (aref ESC-pf index))
- 				  (setq index (1+ index))
- 				(let ((i 0))
- 				  (insert-char 91 1)
- 				  (while (< i index)
- 				    (progn
- 				      (insert-char (aref ESC-pf i) 1)
- 				      (setq i (1+ i))))
- 				  (insert-char char 1)
- 				  (throw 'search-done t)))))
- 			(progn
- 			  (insert-char char 1)
- 			  (throw 'search-done t))))
  		  ;; Esc means exit search normally.
  		  ;; Except, if first thing typed, it means do nonincremental
  		  (if (= 0 (length search-string))
--- 113,118 ----

************* ~/.emacs ********************

....

;;;
;;; Management of the ESC and keypad keys on a vt220
;;;
(defun vt220-setup ()
  (enable-arrow-keys)
  ; in vt220 mode the ESC key produces a different sequence
  (global-unset-key "\e[23~\e")
  (define-key esc-map "\e[23~" 'eval-expression)
  (global-unset-key "\C-x\e")
  (define-key ctl-x-map "\e[23~" 'repeat-complex-command)
  (define-key repeat-complex-command-map "\e[23~p" 'previous-complex-command)
  (define-key repeat-complex-command-map "\e[23~n" 'next-complex-command)
  )

(let ((term (getenv "TERM")))
  (if (or (string-equal term "vt220")
	  (and (eq system-type 'vax-vms)
	       (string-equal term "vt200")))
      (setq term-setup-hook 'vt220-setup)))

.....

_________________________________________________________
Stefano Diomedi
Tecsiel S.p.A.               phone:   +39 (50) 512511
Via Santa Maria 19           fax:     +39 (50) 589015
I-56126 Pisa - ITALY         e-mail:  sdiomedi@tecsiel.it