;;; vt100.el --- define VT100 function key sequences in function-key-map

;; Copyright (C) 1989, 1993, 2001-2019 Free Software Foundation, Inc.

;; Author: FSF
;; Keywords: terminals

;; 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 3 of the License, 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.  If not, see <https://www.gnu.org/licenses/>.

;;; Commentary:

;; Handles all VT100 clones, including the Apollo terminal.  Also handles
;; the VT200 --- its PF- and arrow- keys are different, but all those
;; are really set up by the terminal initialization code, which mines them
;; out of termcap.  This package is here to define the keypad comma, dash
;; and period (which aren't in termcap's repertoire) and the function for
;; changing from 80 to 132 columns & vv.

;;; Code:

;; Set up function-key-map entries that termcap and terminfo don't know.

(defun terminal-init-vt100 ()
  "Terminal initialization function for vt100."
  (tty-run-terminal-initialization (selected-frame) "lk201"))

;;; Controlling the screen width.
(define-minor-mode vt100-wide-mode
  "Toggle 132/80 column mode for vt100s.
With a prefix argument ARG, switch to 132-column mode if ARG is
positive, and 80-column mode otherwise.  If called from Lisp,
switch to 132-column mode if ARG is omitted or nil."
  :global t :init-value (= (frame-width) 132)
  :group 'terminals
  (send-string-to-terminal (if vt100-wide-mode "\e[?3h" "\e[?3l"))
  (set-frame-width terminal-frame (if vt100-wide-mode 132 80)))

(provide 'term/vt100)

;;; vt100.el ends here
