lisp/vt-control.el

   1 ;;; vt-control.el --- Common VTxxx control functions
   2
   3 ;; Copyright (C) 1993, 1994, 2001, 2002, 2003,
   4 ;;   2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
   5
   6 ;; Author: Rob Riepel <riepel@networking.stanford.edu>
   7 ;; Maintainer: Rob Riepel <riepel@networking.stanford.edu>
   8 ;; Keywords: terminals
   9
  10 ;; This file is part of GNU Emacs.
  11
  12 ;; GNU Emacs is free software: you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation, either version 3 of the License, or
  15 ;; (at your option) any later version.
  16
  17 ;; GNU Emacs is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  24
  25 ;;; Commentary:
  26
  27 ;;  The functions contained in this file send various VT control codes
  28 ;;  to the terminal where emacs is running.  The following functions are
  29 ;;  available.
  30
  31 ;;    Function           Action
  32
  33 ;;    vt-wide            set wide screen (132 characters)
  34 ;;    vt-narrow          set narrow screen (80 characters)
  35 ;;    vt-toggle-screen   toggle wide/narrow screen
  36 ;;    vt-keypad-on       set applications keypad on
  37 ;;    vt-keypad-off      set applications keypad off
  38 ;;    vt-numlock         toggle applications keypad on/off
  39
  40 ;;; Usage:
  41
  42 ;;  To use enable these functions, simply load this file.
  43
  44 ;;  Note: vt-control makes no effort to determine how the terminal is
  45 ;;        initially set.  It assumes the terminal starts with a width
  46 ;;        of 80 characters and the applications keypad enabled.  Nor
  47 ;;        does vt-control try to restore the terminal when emacs is
  48 ;;        killed or suspended.
  49
  50 ;;; Code:
  51
  52
  53 ;;;  Global variables
  54
  55 (defvar vt-applications-keypad-p t
  56   "If non-nil, keypad is in applications mode.")
  57
  58 (defvar vt-wide-p nil
  59   "If non-nil, the screen is 132 characters wide.")
  60
  61
  62 ;;;  Screen width functions.
  63
  64 (defun vt-wide nil
  65   "Set the screen 132 characters wide."
  66   (interactive)
  67   (send-string-to-terminal "\e[?3h")
  68   (set-frame-width (selected-frame) 132)
  69   (setq vt-wide-p t))
  70
  71 (defun vt-narrow nil
  72   "Set the screen 80 characters wide."
  73   (interactive)
  74   (send-string-to-terminal "\e[?3l")
  75   (set-frame-width (selected-frame) 80)
  76   (setq vt-wide-p nil))
  77
  78 (defun vt-toggle-screen nil
  79   "Toggle between 80 and 132 character screen width."
  80   (interactive)
  81   (if vt-wide-p (vt-narrow) (vt-wide)))
  82
  83
  84 ;;;  Applications keypad functions.
  85
  86 (defun vt-keypad-on (&optional tell)
  87   "Turn on the VT applications keypad."
  88   (interactive)
  89   (send-string-to-terminal "\e=")
  90   (setq vt-applications-keypad-p t)
  91   (if (or tell (called-interactively-p 'interactive))
  92       (message "Applications keypad enabled.")))
  93
  94 (defun vt-keypad-off (&optional tell)
  95   "Turn off the VT applications keypad."
  96   (interactive "p")
  97   (send-string-to-terminal "\e>")
  98   (setq vt-applications-keypad-p nil)
  99   (if (or tell (called-interactively-p 'interactive))
 100       (message "Applications keypad disabled.")))
 101
 102 (defun vt-numlock nil
 103   "Toggle VT application keypad on and off."
 104   (interactive)
 105   (if vt-applications-keypad-p
 106       (vt-keypad-off (called-interactively-p 'interactive))
 107     (vt-keypad-on (called-interactively-p 'interactive))))
 108
 109 (provide 'vt-control)
 110
 111 ;; arch-tag: d4fed1bf-2524-4ba1-a4fe-86bca3d928a2
 112 ;;; vt-control.el ends here