lisp/vt-control.el

   1 ;;; vt-control.el --- Common VTxxx control functions
   2
   3 ;; Copyright (C) 1993 Free Software Foundation, Inc.
   4
   5 ;; Author: Rob Riepel <riepel@networking.stanford.edu>
   6 ;; Maintainer: Rob Riepel <riepel@networking.stanford.edu>
   7 ;; Keywords: vt100
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 2, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to
  23 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  24
  25 ;;; Revision: $Id: vt-control.el,v 2.2 1993/08/01 21:47:43 riepel Exp $
  26
  27 ;;; Commentary:
  28
  29 ;;  The functions contained in this file send various VT control codes
  30 ;;  to the terminal where emacs is running.  The following functions are
  31 ;;  available.
  32
  33 ;;    Function           Action
  34
  35 ;;    vt-wide            set wide screen (132 characters)
  36 ;;    vt-narrow          set narrow screen (80 characters)
  37 ;;    vt-toggle-screen   toggle wide/narrow screen
  38 ;;    vt-keypad-on       set applications keypad on
  39 ;;    vt-keypad-off      set applications keypad off
  40 ;;    vt-numlock         toggle applications keypad on/off
  41
  42 ;;; Usage:
  43
  44 ;;  To use enable these functions, simply load this file.
  45
  46 ;;  Note: vt-control makes no effort to determine how the terminal is
  47 ;;        initially set.  It assumes the terminal starts with a width
  48 ;;        of 80 characters and the applications keypad enabled.  Nor
  49 ;;        does vt-control try to restore the terminal when emacs is
  50 ;;        killed or suspended.
  51
  52 ;;; Code:
  53
  54
  55 ;;;  Revision Information
  56
  57 (defconst vt-revision "$Revision: 2.2 $"
  58   "Revision number of vt-control.")
  59
  60
  61 ;;;  Global variables
  62
  63 (defvar vt-applications-keypad-p t
  64   "If non-nil, keypad is in applications mode.")
  65
  66 (defvar vt-wide-p nil
  67   "If non-nil, the screen is 132 characters wide.")
  68
  69
  70 ;;;  Screen width functions.
  71
  72 (defun vt-wide nil
  73   "Set the screen 132 characters wide."
  74   (interactive)
  75   (send-string-to-terminal "\e[?3h")
  76   (set-screen-width 132)
  77   (setq vt-wide-p t))
  78
  79 (defun vt-narrow nil
  80   "Set the screen 80 characters wide."
  81   (interactive)
  82   (send-string-to-terminal "\e[?3l")
  83   (set-screen-width 80)
  84   (setq vt-wide-p nil))
  85
  86 (defun vt-toggle-screen nil
  87   "Toggle between 80 and 132 character screen width."
  88   (interactive)
  89   (if vt-wide-p (vt-narrow) (vt-wide)))
  90
  91
  92 ;;;  Applications keypad functions.
  93
  94 (defun vt-keypad-on (&optional tell)
  95   "Turn on the VT applications keypad."
  96   (interactive)
  97   (send-string-to-terminal "\e[\e=")
  98   (setq vt-applications-keypad-p t)
  99   (if (or tell (interactive-p)) (message "Applications keypad enabled.")))
 100
 101 (defun vt-keypad-off (&optional tell)
 102   "Turn off the VT applications keypad."
 103   (interactive "p")
 104   (send-string-to-terminal "\e[\e>")
 105   (setq vt-applications-keypad-p nil)
 106   (if (or tell (interactive-p)) (message "Applications keypad disabled.")))
 107
 108 (defun vt-numlock nil
 109   "Toggle VT application keypad on and off."
 110   (interactive)
 111   (if vt-applications-keypad-p (vt-keypad-off (interactive-p))
 112     (vt-keypad-on (interactive-p))))
 113
 114 ;;; vt-control.el ends here