mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-12-29 11:02:01 +00:00
127 lines
5.0 KiB
EmacsLisp
127 lines
5.0 KiB
EmacsLisp
;;; flow-ctrl.el --- help for lusers on cu(1) or ttys with wired-in ^S/^Q flow control
|
|
|
|
;; Copyright (C) 1990, 1991, 1994 Free Software Foundation, Inc.
|
|
|
|
;; Author Kevin Gallagher
|
|
;; Maintainer: FSF
|
|
;; Adapted-By: ESR
|
|
;; Keywords: hardware
|
|
|
|
;; 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 2, 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, Inc., 59 Temple Place - Suite 330,
|
|
;; Boston, MA 02111-1307, USA.
|
|
|
|
;;; Commentary:
|
|
|
|
;; Terminals that use XON/XOFF flow control can cause problems with
|
|
;; GNU Emacs users. This file contains Emacs Lisp code that makes it
|
|
;; easy for a user to deal with this problem, when using such a
|
|
;; terminal.
|
|
;;
|
|
;; To invoke these adjustments, a user need only invoke the function
|
|
;; enable-flow-control-on with a list of terminal types in his/her own
|
|
;; .emacs file. As arguments, give it the names of one or more terminal
|
|
;; types in use by that user which require flow control adjustments.
|
|
;; Here's an example:
|
|
;;
|
|
;; (enable-flow-control-on "vt200" "vt300" "vt101" "vt131")
|
|
|
|
;; Portability note: This uses (getenv "TERM"), and therefore probably
|
|
;; won't work outside of UNIX-like environments.
|
|
|
|
;;; Code:
|
|
|
|
(defvar flow-control-c-s-replacement ?\034
|
|
"Character that replaces C-s, when flow control handling is enabled.")
|
|
(defvar flow-control-c-q-replacement ?\036
|
|
"Character that replaces C-q, when flow control handling is enabled.")
|
|
|
|
(put 'keyboard-translate-table 'char-table-extra-slots 0)
|
|
|
|
;;;###autoload
|
|
(defun enable-flow-control (&optional argument)
|
|
"Toggle flow control handling.
|
|
When handling is enabled, user can type C-s as C-\\, and C-q as C-^.
|
|
With arg, enable flow control mode if arg is positive, otherwise disable."
|
|
(interactive "P")
|
|
(if (if argument
|
|
;; Argument means enable if arg is positive.
|
|
(<= (prefix-numeric-value argument) 0)
|
|
;; No arg means toggle.
|
|
(nth 1 (current-input-mode)))
|
|
(progn
|
|
;; Turn flow control off, and stop exchanging chars.
|
|
(set-input-mode t nil (nth 2 (current-input-mode)))
|
|
(if keyboard-translate-table
|
|
(progn
|
|
(aset keyboard-translate-table flow-control-c-s-replacement nil)
|
|
(aset keyboard-translate-table ?\^s nil)
|
|
(aset keyboard-translate-table flow-control-c-q-replacement nil)
|
|
(aset keyboard-translate-table ?\^q nil))))
|
|
;; Turn flow control on.
|
|
;; Tell emacs to pass C-s and C-q to OS.
|
|
(set-input-mode nil t (nth 2 (current-input-mode)))
|
|
;; Initialize translate table, saving previous mappings, if any.
|
|
(cond ((null keyboard-translate-table)
|
|
(setq keyboard-translate-table
|
|
(make-char-table 'keyboard-translate-table nil)))
|
|
((char-table-p keyboard-translate-table)
|
|
(setq keyboard-translate-table
|
|
(copy-sequence keyboard-translate-table)))
|
|
(t
|
|
(let ((the-table (make-char-table 'keyboard-translate-table nil)))
|
|
(let ((i 0)
|
|
(j (length keyboard-translate-table)))
|
|
(while (< i j)
|
|
(aset the-table i (elt keyboard-translate-table i))
|
|
(setq i (1+ i))))
|
|
(setq keyboard-translate-table the-table))))
|
|
;; Swap C-s and C-\
|
|
(aset keyboard-translate-table flow-control-c-s-replacement ?\^s)
|
|
(aset keyboard-translate-table ?\^s flow-control-c-s-replacement)
|
|
;; Swap C-q and C-^
|
|
(aset keyboard-translate-table flow-control-c-q-replacement ?\^q)
|
|
(aset keyboard-translate-table ?\^q flow-control-c-q-replacement)
|
|
(message "XON/XOFF adjustment for %s: use %s for C-s, and use %s for C-q"
|
|
(getenv "TERM")
|
|
(single-key-description flow-control-c-s-replacement)
|
|
(single-key-description flow-control-c-q-replacement))
|
|
(sleep-for 2))) ; Give user a chance to see message.
|
|
|
|
;;;###autoload
|
|
(defun enable-flow-control-on (&rest losing-terminal-types)
|
|
"Enable flow control if using one of a specified set of terminal types.
|
|
Use `(enable-flow-control-on \"vt100\" \"h19\")' to enable flow control
|
|
on VT-100 and H19 terminals. When flow control is enabled,
|
|
you must type C-\\ to get the effect of a C-s, and type C-^
|
|
to get the effect of a C-q."
|
|
(let ((term (getenv "TERM"))
|
|
hyphend)
|
|
;; Look for TERM in LOSING-TERMINAL-TYPES.
|
|
;; If we don't find it literally, try stripping off words
|
|
;; from the end, one by one.
|
|
(while (and term (not (member term losing-terminal-types)))
|
|
;; Strip off last hyphen and what follows, then try again.
|
|
(if (setq hyphend (string-match "[-_][^-_]+$" term))
|
|
(setq term (substring term 0 hyphend))
|
|
(setq term nil)))
|
|
(if term
|
|
(enable-flow-control))))
|
|
|
|
(provide 'flow-ctrl)
|
|
|
|
;;; flow-ctrl.el ends here
|