[bpt/emacs.git] / lisp / vt100-led.el

;; Functions for controlling the LEDs on VT-100 terminals & clones.
;; Copyright (C) 1988 Free Software Foundation, Inc.

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 1, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to
;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.


;; Written by Howard Gayle.

(defvar led-state (make-vector 5 nil)
   "The internal state of the LEDs.  Choices are nil, t, `flash.
Element 0 is not used.")

(defun led-flash (l)
  "Flash LED l."
  (aset led-state l 'flash)
  (led-update))

(defun led-off (&optional l)
  "Turn off vt100 led number L.  With no argument, turn them all off."
  (interactive "P")
  (if l
      (aset led-state (prefix-numeric-value l) nil)
    (fillarray led-state nil))
  (led-update))

(defun led-on (l)
  "Turn on LED l."
  (aset led-state l t)
  (led-update))

(defun led-update ()
  "Update the terminal's LEDs to reflect the internal state."
  (let ((f "\e[?0")			; String to flash.
	(o "\e[0")			; String for steady on.
	(l 1))				; Current LED number.
    (while (/= l 5)
      (let ((s (aref led-state l)))
	(cond
	 ((eq s 'flash)
	  (setq f (concat f ";" (int-to-string l))))
	 (s
	  (setq o (concat o ";" (int-to-string l))))))
      (setq l (1+ l)))
    (setq o (concat o "q" f "t"))
    (send-string-to-terminal o)))

(provide 'vt100-led)
Commit	Line	Data
3b4a6e27 JB	1	;; Functions for controlling the LEDs on VT-100 terminals & clones.
	2	;; Copyright (C) 1988 Free Software Foundation, Inc.
	3
	4	;; This file is part of GNU Emacs.
	5
	6	;; GNU Emacs is free software; you can redistribute it and/or modify
	7	;; it under the terms of the GNU General Public License as published by
	8	;; the Free Software Foundation; either version 1, or (at your option)
	9	;; any later version.
	10
	11	;; GNU Emacs is distributed in the hope that it will be useful,
	12	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	;; GNU General Public License for more details.
	15
	16	;; You should have received a copy of the GNU General Public License
	17	;; along with GNU Emacs; see the file COPYING. If not, write to
	18	;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
	19
	20
	21	;; Written by Howard Gayle.
	22
	23	(defvar led-state (make-vector 5 nil)
	24	"The internal state of the LEDs. Choices are nil, t, `flash.
	25	Element 0 is not used.")
	26
	27	(defun led-flash (l)
	28	"Flash LED l."
	29	(aset led-state l 'flash)
	30	(led-update))
	31
	32	(defun led-off (&optional l)
	33	"Turn off vt100 led number L. With no argument, turn them all off."
	34	(interactive "P")
	35	(if l
	36	(aset led-state (prefix-numeric-value l) nil)
	37	(fillarray led-state nil))
	38	(led-update))
	39
	40	(defun led-on (l)
	41	"Turn on LED l."
	42	(aset led-state l t)
	43	(led-update))
	44
	45	(defun led-update ()
	46	"Update the terminal's LEDs to reflect the internal state."
	47	(let ((f "\e[?0") ; String to flash.
	48	(o "\e[0") ; String for steady on.
	49	(l 1)) ; Current LED number.
	50	(while (/= l 5)
	51	(let ((s (aref led-state l)))
	52	(cond
	53	((eq s 'flash)
	54	(setq f (concat f ";" (int-to-string l))))
	55	(s
	56	(setq o (concat o ";" (int-to-string l))))))
	57	(setq l (1+ l)))
	58	(setq o (concat o "q" f "t"))
	59	(send-string-to-terminal o)))
	60
	61	(provide 'vt100-led)