;;; term.el --- general command interpreter in a window stuff

;; Copyright (C) 1988, 1990, 1992, 1994, 1995 Free Software Foundation, Inc.

;; Author: Per Bothner <bothner@cygnus.com>
;; Based on comint mode written by: Olin Shivers <shivers@cs.cmu.edu>
;; Keyword: processes

;; 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:

;; The changelog is at the end of this file.

;; Please send me bug reports, bug fixes, and extensions, so that I can
;; merge them into the master source.
;;     - Per Bothner (bothner@cygnus.com)

;; This file defines a general command-interpreter-in-a-buffer package
;; (term mode). The idea is that you can build specific process-in-a-buffer
;; modes on top of term mode -- e.g., lisp, shell, scheme, T, soar, ....
;; This way, all these specific packages share a common base functionality, 
;; and a common set of bindings, which makes them easier to use (and
;; saves code, implementation time, etc., etc.).

;; For hints on converting existing process modes (e.g., tex-mode,
;; background, dbx, gdb, kermit, prolog, telnet) to use term-mode
;; instead of shell-mode, see the notes at the end of this file.


;; Brief Command Documentation:
;;============================================================================
;; Term Mode Commands: (common to all derived modes, like cmushell & cmulisp
;; mode)
;;
;; m-p	    term-previous-input    	  Cycle backwards in input history
;; m-n	    term-next-input  	    	  Cycle forwards
;; m-r     term-previous-matching-input  Previous input matching a regexp
;; m-s     comint-next-matching-input      Next input that matches
;; return  term-send-input
;; c-c c-a term-bol                      Beginning of line; skip prompt.
;; c-d	    term-delchar-or-maybe-eof     Delete char unless at end of buff.
;; c-c c-u term-kill-input	    	    ^u
;; c-c c-w backward-kill-word    	    ^w
;; c-c c-c term-interrupt-subjob 	    ^c
;; c-c c-z term-stop-subjob	    	    ^z
;; c-c c-\ term-quit-subjob	    	    ^\
;; c-c c-o term-kill-output		    Delete last batch of process output
;; c-c c-r term-show-output		    Show last batch of process output
;; c-c c-h term-dynamic-list-input-ring  List input history
;;
;; Not bound by default in term-mode
;; term-send-invisible			Read a line w/o echo, and send to proc
;; (These are bound in shell-mode)
;; term-dynamic-complete		Complete filename at point.
;; term-dynamic-list-completions	List completions in help buffer.
;; term-replace-by-expanded-filename	Expand and complete filename at point;
;;					replace with expanded/completed name.
;; term-kill-subjob			No mercy.
;; term-show-maximum-output            Show as much output as possible.
;; term-continue-subjob		Send CONT signal to buffer's process
;;					group. Useful if you accidentally
;;					suspend your process (with C-c C-z).

;; term-mode-hook is the term mode hook. Basically for your keybindings.
;; term-load-hook is run after loading in this package.

;; Code:

;; This is passed to the inferior in the EMACS environment variable,
;; so it is important to increase it if there are protocol-relevant changes.
(defconst term-protocol-version "0.95")

(require 'ring)
(require 'ehelp)

;;; Buffer Local Variables:
;;;============================================================================
;;; Term mode buffer local variables:
;;;     term-prompt-regexp    - string       term-bol uses to match prompt.
;;;     term-delimiter-argument-list - list  For delimiters and arguments
;;;     term-last-input-start - marker       Handy if inferior always echoes
;;;     term-last-input-end   - marker       For term-kill-output command
;; For the input history mechanism:
(defvar term-input-ring-size 32 "Size of input history ring.")
;;;     term-input-ring-size  - integer
;;;     term-input-ring       - ring
;;;     term-input-ring-index - number           ...
;;;     term-input-autoexpand - symbol           ...
;;;     term-input-ignoredups - boolean          ...
;;;     term-last-input-match - string           ...
;;;     term-dynamic-complete-functions - hook   For the completion mechanism
;;;     term-completion-fignore - list           ...
;;;     term-get-old-input    - function     Hooks for specific 
;;;     term-input-filter-functions - hook     process-in-a-buffer
;;;     term-input-filter     - function         modes.
;;;     term-input-send	- function
;;;     term-scroll-to-bottom-on-output - symbol ...
;;;     term-scroll-show-maximum-output - boolean...
(defvar term-height) ;; Number of lines in window.
(defvar term-width) ;; Number of columns in window.
(defvar term-home-marker) ;; Marks the "home" position for cursor addressing.
(defvar term-saved-home-marker nil) ;; When using alternate sub-buffer,
;;		contains saved term-home-marker from original sub-buffer .
(defvar term-start-line-column 0) ;; (current-column) at start of screen line,
;;		or nil if unknown.
(defvar term-current-column 0) ;; If non-nil, is cache for (current-column).
(defvar term-current-row 0) ;; Current vertical row (relative to home-marker)
;;		or nil if unknown.
(defvar term-insert-mode nil)
(defvar term-vertical-motion)
(defvar term-terminal-state 0) ;; State of the terminal emulator:
;;		state 0: Normal state
;;		state 1: Last character was a graphic in the last column.
;;		If next char is graphic, first move one column right
;;		(and line warp) before displaying it.
;;		This emulates (more or less) the behavior of xterm.
;;		state 2: seen ESC
;;		state 3: seen ESC [ (or ESC [ ?)
;;		state 4: term-terminal-parameter contains pending output.
(defvar term-kill-echo-list nil) ;; A queue of strings whose echo
;;		we want suppressed.
(defvar term-terminal-parameter)
(defvar term-terminal-previous-parameter)
(defvar term-current-face 'default)
(defvar term-scroll-start 0) ;; Top-most line (inclusive) of scrolling region.
(defvar term-scroll-end) ;; Number of line (zero-based) after scrolling region.
(defvar term-pager-count nil) ;; If nil, paging is disabled.
;;		Otherwise, number of lines before we need to page.
(defvar term-saved-cursor nil)
(defvar term-command-hook)
(defvar term-log-buffer nil)
(defvar term-scroll-with-delete nil) ;; term-scroll-with-delete is t if
;;		forward scrolling should be implemented by delete to
;;		top-most line(s); and nil if scrolling should be implemented
;;		by moving term-home-marker.  It is set to t iff there is a
;;		(non-default) scroll-region OR the alternate buffer is used.
(defvar term-pending-delete-marker) ;; New user input in line mode needs to
;;		be deleted, because it gets echoed by the inferior.
;;		To reduce flicker, we defer the delete until the next output.
(defvar term-old-mode-map nil) ;; Saves the old keymap when in char mode.
(defvar term-old-mode-line-format) ;; Saves old mode-line-format while paging.
(defvar term-pager-old-local-map nil) ;; Saves old keymap while paging.
(defvar term-pager-old-filter) ;; Saved process-filter while paging.

(defvar explicit-shell-file-name nil
  "*If non-nil, is file name to use for explicitly requested inferior shell.")

(defvar term-prompt-regexp "^"
  "Regexp to recognise prompts in the inferior process.
Defaults to \"^\", the null string at BOL.

Good choices:
  Canonical Lisp: \"^[^> \\n]*>+:? *\" (Lucid, franz, kcl, T, cscheme, oaklisp)
  Lucid Common Lisp: \"^\\\\(>\\\\|\\\\(->\\\\)+\\\\) *\"
  franz: \"^\\\\(->\\\\|<[0-9]*>:\\\\) *\"
  kcl: \"^>+ *\"
  shell: \"^[^#$%>\\n]*[#$%>] *\"
  T: \"^>+ *\"

This is a good thing to set in mode hooks.")

(defvar term-delimiter-argument-list ()
  "List of characters to recognise as separate arguments in input.
Strings comprising a character in this list will separate the arguments
surrounding them, and also be regarded as arguments in their own right (unlike
whitespace).  See `term-arguments'.
Defaults to the empty list.

For shells, a good value is (?\\| ?& ?< ?> ?\\( ?\\) ?;).

This is a good thing to set in mode hooks.")

(defvar term-input-autoexpand nil
  "*If non-nil, expand input command history references on completion.
This mirrors the optional behavior of tcsh (its autoexpand and histlit).

If the value is `input', then the expansion is seen on input.
If the value is `history', then the expansion is only when inserting
into the buffer's input ring.  See also `term-magic-space' and
`term-dynamic-complete'.

This variable is buffer-local.")

(defvar term-input-ignoredups nil
  "*If non-nil, don't add input matching the last on the input ring.
This mirrors the optional behavior of bash.

This variable is buffer-local.")

(defvar term-input-ring-file-name nil
  "*If non-nil, name of the file to read/write input history.
See also `term-read-input-ring' and `term-write-input-ring'.

This variable is buffer-local, and is a good thing to set in mode hooks.")

(defvar term-scroll-to-bottom-on-output nil
  "*Controls whether interpreter output causes window to scroll.
If nil, then do not scroll.  If t or `all', scroll all windows showing buffer.
If `this', scroll only the selected window.
If `others', scroll only those that are not the selected window.

The default is nil.

See variable `term-scroll-show-maximum-output'.
This variable is buffer-local.")

(defvar term-scroll-show-maximum-output nil
  "*Controls how interpreter output causes window to scroll.
If non-nil, then show the maximum output when the window is scrolled.

See variable `term-scroll-to-bottom-on-output'.
This variable is buffer-local.")

;; Where gud-display-frame should put the debugging arrow.  This is
;; set by the marker-filter, which scans the debugger's output for
;; indications of the current pc.
(defvar term-pending-frame nil)

;;; Here are the per-interpreter hooks.
(defvar term-get-old-input (function term-get-old-input-default)
  "Function that submits old text in term mode.
This function is called when return is typed while the point is in old text.
It returns the text to be submitted as process input.  The default is
term-get-old-input-default, which grabs the current line, and strips off
leading text matching term-prompt-regexp")

(defvar term-dynamic-complete-functions
  '(term-replace-by-expanded-history term-dynamic-complete-filename)
  "List of functions called to perform completion.
Functions should return non-nil if completion was performed.
See also `term-dynamic-complete'.

This is a good thing to set in mode hooks.")

(defvar term-input-filter
  (function (lambda (str) (not (string-match "\\`\\s *\\'" str))))
  "Predicate for filtering additions to input history.
Only inputs answering true to this function are saved on the input
history list. Default is to save anything that isn't all whitespace")

(defvar term-input-filter-functions '()
  "Functions to call before input is sent to the process.
These functions get one argument, a string containing the text to send.

This variable is buffer-local.")

(defvar term-input-sender (function term-simple-send)
  "Function to actually send to PROCESS the STRING submitted by user.
Usually this is just 'term-simple-send, but if your mode needs to 
massage the input string, this is your hook. This is called from
the user command term-send-input. term-simple-send just sends
the string plus a newline.")

(defvar term-eol-on-send t
  "*Non-nil means go to the end of the line before sending input.
See `term-send-input'.")

(defvar term-mode-hook '()
  "Called upon entry into term-mode
This is run before the process is cranked up.")

(defvar term-exec-hook '()
  "Called each time a process is exec'd by term-exec.
This is called after the process is cranked up.  It is useful for things that
must be done each time a process is executed in a term-mode buffer (e.g.,
\(process-kill-without-query)). In contrast, the term-mode-hook is only
executed once when the buffer is created.")

(defvar term-mode-map nil)
(defvar term-raw-map nil
  "Keyboard map for sending characters directly to the inferior process.")
(defvar term-escape-char nil
  "Escape character for char-sub-mode of term mode.
Do not change it directly;  use term-set-escape-char instead.")
(defvar term-raw-escape-map nil)

(defvar term-pager-break-map nil)

(defvar term-ptyp t
  "True if communications via pty; false if by pipe.  Buffer local.
This is to work around a bug in emacs process signaling.")

(defvar term-last-input-match ""
  "Last string searched for by term input history search, for defaulting.
Buffer local variable.") 

(defvar term-input-ring nil)
(defvar term-last-input-start)
(defvar term-last-input-end)
(defvar term-input-ring-index nil
  "Index of last matched history element.")
(defvar term-matching-input-from-input-string ""
  "Input previously used to match input history.")
; This argument to set-process-filter disables reading from the process,
; assuming this is emacs-19.20 or newer.
(defvar term-pager-filter t)

(put 'term-replace-by-expanded-history 'menu-enable 'term-input-autoexpand)
(put 'term-input-ring 'permanent-local t)
(put 'term-input-ring-index 'permanent-local t)
(put 'term-input-autoexpand 'permanent-local t)
(put 'term-input-filter-functions 'permanent-local t)
(put 'term-scroll-to-bottom-on-output 'permanent-local t)
(put 'term-scroll-show-maximum-output 'permanent-local t)
(put 'term-ptyp 'permanent-local t)

;; Do FORMS if running under Emacs-19.
(defmacro term-if-emacs19 (&rest forms)
  (if (string-match "^19" emacs-version) (cons 'progn forms)))
;; True if running under XEmacs (previously Lucid emacs).
(defmacro term-is-xemacs ()  '(string-match "Lucid" emacs-version))
;; Do FORM if running under XEmacs (previously Lucid emacs).
(defmacro term-if-xemacs (&rest forms)
  (if (term-is-xemacs) (cons 'progn forms)))
;; Do FORM if NOT running under XEmacs (previously Lucid emacs).
(defmacro term-ifnot-xemacs (&rest forms)
  (if (not (term-is-xemacs)) (cons 'progn forms)))

(defmacro term-in-char-mode () '(eq (current-local-map) term-raw-map))
(defmacro term-in-line-mode () '(not (term-in-char-mode)))
;; True if currently doing PAGER handling.
(defmacro term-pager-enabled () 'term-pager-count)
(defmacro term-handling-pager () 'term-pager-old-local-map)
(defmacro term-using-alternate-sub-buffer () 'term-saved-home-marker)

(defvar term-signals-menu)
(defvar term-terminal-menu)

(term-if-xemacs
 (defvar term-terminal-menu
   '("Terminal"
     [ "Character mode" term-char-mode (term-in-line-mode)]
     [ "Line mode" term-line-mode (term-in-char-mode)]
     [ "Enable paging" term-pager-toggle (not term-pager-count)]
     [ "Disable paging" term-pager-toggle term-pager-count])))

(defun term-mode ()
  "Major mode for interacting with an inferior interpreter.
Interpreter name is same as buffer name, sans the asterisks.
In line sub-mode, return at end of buffer sends line as input,
while return not at end copies rest of line to end and sends it.
In char sub-mode, each character (except `term-escape-char`) is
set immediately.

This mode is typically customised to create inferior-lisp-mode,
shell-mode, etc.. This can be done by setting the hooks
term-input-filter-functions, term-input-filter, term-input-sender and
term-get-old-input to appropriate functions, and the variable
term-prompt-regexp to the appropriate regular expression.

An input history is maintained of size `term-input-ring-size', and
can be accessed with the commands \\[term-next-input], \\[term-previous-input], and \\[term-dynamic-list-input-ring].
Input ring history expansion can be achieved with the commands
\\[term-replace-by-expanded-history] or \\[term-magic-space].
Input ring expansion is controlled by the variable `term-input-autoexpand',
and addition is controlled by the variable `term-input-ignoredups'.

Input to, and output from, the subprocess can cause the window to scroll to
the end of the buffer.  See variables `term-scroll-to-bottom-on-input',
and `term-scroll-to-bottom-on-output'.

If you accidentally suspend your process, use \\[term-continue-subjob]
to continue it.

\\{term-mode-map}

Entry to this mode runs the hooks on term-mode-hook"
  (interactive)
    ;; Do not remove this.  All major modes must do this.
    (kill-all-local-variables)
    (setq major-mode 'term-mode)
    (setq mode-name "Term")
    (use-local-map term-mode-map)
    (make-local-variable 'term-home-marker)
    (setq term-home-marker (copy-marker 0))
    (make-local-variable 'term-saved-home-marker)
    (make-local-variable 'term-height)
    (make-local-variable 'term-width)
    (setq term-width (1- (window-width)))
    (setq term-height (1- (window-height)))
    (make-local-variable 'term-terminal-parameter)
    (make-local-variable 'term-saved-cursor)
    (make-local-variable 'term-last-input-start)
    (setq term-last-input-start (make-marker))
    (make-local-variable 'term-last-input-end)
    (setq term-last-input-end (make-marker))
    (make-local-variable 'term-last-input-match)
    (setq term-last-input-match "")
    (make-local-variable 'term-prompt-regexp)        ; Don't set; default
    (make-local-variable 'term-input-ring-size)      ; ...to global val.
    (make-local-variable 'term-input-ring)
    (make-local-variable 'term-input-ring-file-name)
    (or (and (boundp 'term-input-ring) term-input-ring)
	(setq term-input-ring (make-ring term-input-ring-size)))
    (make-local-variable 'term-input-ring-index)
    (or (and (boundp 'term-input-ring-index) term-input-ring-index)
	(setq term-input-ring-index nil))

    (make-local-variable 'term-command-hook)
    (setq term-command-hook (symbol-function 'term-command-hook))

    (make-local-variable 'term-terminal-state)
    (make-local-variable 'term-kill-echo-list)
    (make-local-variable 'term-start-line-column)
    (make-local-variable 'term-current-column)
    (make-local-variable 'term-current-row)
    (make-local-variable 'term-log-buffer)
    (make-local-variable 'term-scroll-start)
    (make-local-variable 'term-scroll-end)
    (setq term-scroll-end term-height)
    (make-local-variable 'term-scroll-with-delete)
    (make-local-variable 'term-pager-count)
    (make-local-variable 'term-pager-old-local-map)
    (make-local-variable 'term-old-mode-map)
    (make-local-variable 'term-insert-mode)
    (make-local-variable 'term-dynamic-complete-functions)
    (make-local-variable 'term-completion-fignore)
    (make-local-variable 'term-get-old-input)
    (make-local-variable 'term-matching-input-from-input-string)
    (make-local-variable 'term-input-autoexpand)
    (make-local-variable 'term-input-ignoredups)
    (make-local-variable 'term-delimiter-argument-list)
    (make-local-variable 'term-input-filter-functions)
    (make-local-variable 'term-input-filter)  
    (make-local-variable 'term-input-sender)
    (make-local-variable 'term-eol-on-send)
    (make-local-variable 'term-scroll-to-bottom-on-output)
    (make-local-variable 'term-scroll-show-maximum-output)
    (make-local-variable 'term-ptyp)
    (make-local-variable 'term-exec-hook)
    (make-local-variable 'term-vertical-motion)
    (make-local-variable 'term-pending-delete-marker)
    (setq term-pending-delete-marker (make-marker))
    (make-local-variable 'term-current-face)
    (make-local-variable 'term-pending-frame)
    (setq term-pending-frame nil)
    (run-hooks 'term-mode-hook)
    (term-if-xemacs
     (set-buffer-menubar
      (append current-menubar (list term-terminal-menu))))
    (or term-input-ring
	(setq term-input-ring (make-ring term-input-ring-size)))
    (term-update-mode-line))

(if term-mode-map
    nil
  (setq term-mode-map (make-sparse-keymap))
  (define-key term-mode-map "\ep" 'term-previous-input)
  (define-key term-mode-map "\en" 'term-next-input)
  (define-key term-mode-map "\er" 'term-previous-matching-input)
  (define-key term-mode-map "\es" 'term-next-matching-input)
  (term-ifnot-xemacs
   (define-key term-mode-map [?\A-\M-r] 'term-previous-matching-input-from-input)
   (define-key term-mode-map [?\A-\M-s] 'term-next-matching-input-from-input))
  (define-key term-mode-map "\e\C-l" 'term-show-output)
  (define-key term-mode-map "\C-m" 'term-send-input)
  (define-key term-mode-map "\C-d" 'term-delchar-or-maybe-eof)
  (define-key term-mode-map "\C-c\C-a" 'term-bol)
  (define-key term-mode-map "\C-c\C-u" 'term-kill-input)
  (define-key term-mode-map "\C-c\C-w" 'backward-kill-word)
  (define-key term-mode-map "\C-c\C-c" 'term-interrupt-subjob)
  (define-key term-mode-map "\C-c\C-z" 'term-stop-subjob)
  (define-key term-mode-map "\C-c\C-\\" 'term-quit-subjob)
  (define-key term-mode-map "\C-c\C-m" 'term-copy-old-input)
  (define-key term-mode-map "\C-c\C-o" 'term-kill-output)
  (define-key term-mode-map "\C-c\C-r" 'term-show-output)
  (define-key term-mode-map "\C-c\C-e" 'term-show-maximum-output)
  (define-key term-mode-map "\C-c\C-l" 'term-dynamic-list-input-ring)
  (define-key term-mode-map "\C-c\C-n" 'term-next-prompt)
  (define-key term-mode-map "\C-c\C-p" 'term-previous-prompt)
  (define-key term-mode-map "\C-c\C-d" 'term-send-eof)
  (define-key term-mode-map "\C-c\C-k" 'term-char-mode)
  (define-key term-mode-map "\C-c\C-j" 'term-line-mode)
  (define-key term-mode-map "\C-c\C-q" 'term-pager-toggle)

  (copy-face 'default 'term-underline-face)
  (set-face-underline-p 'term-underline-face t)

;  ;; completion:
;  (define-key term-mode-map [menu-bar completion] 
;    (cons "Complete" (make-sparse-keymap "Complete")))
;  (define-key term-mode-map [menu-bar completion complete-expand]
;    '("Expand File Name" . term-replace-by-expanded-filename))
;  (define-key term-mode-map [menu-bar completion complete-listing]
;    '("File Completion Listing" . term-dynamic-list-filename-completions))
;  (define-key term-mode-map [menu-bar completion complete-file]
;    '("Complete File Name" . term-dynamic-complete-filename))
;  (define-key term-mode-map [menu-bar completion complete]
;    '("Complete Before Point" . term-dynamic-complete))
;  ;; Put them in the menu bar:
;  (setq menu-bar-final-items (append '(terminal completion inout signals)
;				     menu-bar-final-items))
  )

;; Menu bars:
(term-ifnot-xemacs
 (term-if-emacs19

  ;; terminal:
  (let (newmap)
    (setq newmap (make-sparse-keymap "Terminal"))
    (define-key newmap [terminal-pager-enable]
      '("Enable paging" . term-fake-pager-enable))
    (define-key newmap [terminal-pager-disable]
      '("Disable paging" . term-fake-pager-disable))
    (define-key newmap [terminal-char-mode]
      '("Character mode" . term-char-mode))
    (define-key newmap [terminal-line-mode]
      '("Line mode" . term-line-mode))
    (setq term-terminal-menu (cons "Terminal" newmap))

    ;; completion:  (line mode only)
    (defvar term-completion-menu (make-sparse-keymap "Complete"))
    (define-key term-mode-map [menu-bar completion] 
      (cons "Complete" term-completion-menu))
    (define-key term-completion-menu [complete-expand]
      '("Expand File Name" . term-replace-by-expanded-filename))
    (define-key term-completion-menu [complete-listing]
      '("File Completion Listing" . term-dynamic-list-filename-completions))
    (define-key term-completion-menu [menu-bar completion complete-file]
      '("Complete File Name" . term-dynamic-complete-filename))
    (define-key term-completion-menu [menu-bar completion complete]
      '("Complete Before Point" . term-dynamic-complete))

    ;; Input history: (line mode only)
    (defvar term-inout-menu (make-sparse-keymap "In/Out"))
    (define-key term-mode-map [menu-bar inout] 
      (cons "In/Out" term-inout-menu))
    (define-key term-inout-menu [kill-output]
      '("Kill Current Output Group" . term-kill-output))
    (define-key term-inout-menu [next-prompt]
      '("Forward Output Group" . term-next-prompt))
    (define-key term-inout-menu [previous-prompt]
      '("Backward Output Group" . term-previous-prompt))
    (define-key term-inout-menu [show-maximum-output]
      '("Show Maximum Output" . term-show-maximum-output))
    (define-key term-inout-menu [show-output]
      '("Show Current Output Group" . term-show-output))
    (define-key term-inout-menu [kill-input]
      '("Kill Current Input" . term-kill-input))
    (define-key term-inout-menu [copy-input]
      '("Copy Old Input" . term-copy-old-input))
    (define-key term-inout-menu [forward-matching-history]
      '("Forward Matching Input..." . term-forward-matching-input))
    (define-key term-inout-menu [backward-matching-history]
      '("Backward Matching Input..." . term-backward-matching-input))
    (define-key term-inout-menu [next-matching-history]
      '("Next Matching Input..." . term-next-matching-input))
    (define-key term-inout-menu [previous-matching-history]
      '("Previous Matching Input..." . term-previous-matching-input))
    (define-key term-inout-menu [next-matching-history-from-input]
      '("Next Matching Current Input" . term-next-matching-input-from-input))
    (define-key term-inout-menu [previous-matching-history-from-input]
      '("Previous Matching Current Input" . term-previous-matching-input-from-input))
    (define-key term-inout-menu [next-history]
      '("Next Input" . term-next-input))
    (define-key term-inout-menu [previous-history]
      '("Previous Input" . term-previous-input))
    (define-key term-inout-menu [list-history]
      '("List Input History" . term-dynamic-list-input-ring))
    (define-key term-inout-menu [expand-history]
      '("Expand History Before Point" . term-replace-by-expanded-history))

    ;; Signals
    (setq newmap (make-sparse-keymap "Signals"))
    (define-key newmap [eof] '("EOF" . term-send-eof))
    (define-key newmap [kill] '("KILL" . term-kill-subjob))
    (define-key newmap [quit] '("QUIT" . term-quit-subjob))
    (define-key newmap [cont] '("CONT" . term-continue-subjob))
    (define-key newmap [stop] '("STOP" . term-stop-subjob))
    (define-key newmap [] '("BREAK" . term-interrupt-subjob))
    (define-key term-mode-map [menu-bar signals]
      (setq term-signals-menu (cons "Signals" newmap)))
    )))

(defun term-reset-size (height width)
  (setq term-height height)
  (setq term-width width)
  (setq term-start-line-column nil)
  (setq term-current-row nil)
  (setq term-current-column nil)
  (term-scroll-region 0 height))

;; Recursive routine used to check if any string in term-kill-echo-list
;; matches part of the buffer before point.
;; If so, delete that matched part of the buffer - this suppresses echo.
;; Also, remove that string from the term-kill-echo-list.
;; We *also* remove any older string on the list, as a sanity measure,
;; in case something gets out of sync.  (Except for type-ahead, there
;; should only be one element in the list.)

(defun term-check-kill-echo-list ()
  (let ((cur term-kill-echo-list) (found nil) (save-point (point)))
    (unwind-protect
	(progn
	  (end-of-line)
	  (while cur
	    (let* ((str (car cur)) (len (length str)) (start (- (point) len)))
	      (if (and (>= start (point-min))
		       (string= str (buffer-substring start (point))))
		  (progn (delete-backward-char len)
			 (setq term-kill-echo-list (cdr cur))
			 (setq term-current-column nil)
			 (setq term-current-row nil)
			 (setq term-start-line-column nil)
			 (setq cur nil found t))
		(setq cur (cdr cur))))))
      (if (not found)
	  (goto-char save-point)))
    found))

(defun term-check-size (process)
  (if (or (/= term-height (1- (window-height)))
	  (/= term-width (1- (window-width))))
      (progn
	(term-reset-size (1- (window-height)) (1- (window-width)))
	(set-process-window-size process term-height term-width))))

(defun term-send-raw-string (chars)
  (let ((proc (get-buffer-process (current-buffer))))
    (if (not proc)
	(error "Current buffer has no process")
      ;; Note that (term-current-row) must be called *after*
      ;; (point) has been updated to (process-mark proc).
      (goto-char (process-mark proc))
      (if (term-pager-enabled)
	  (setq term-pager-count (term-current-row)))
      (process-send-string proc chars))))

(defun term-send-raw ()
  "Send the last character typed through the terminal-emulator
without any interpretation." 
  (interactive)
 ;; Convert `return' to C-m, etc.
  (if (and (symbolp last-input-char)
	   (get last-input-char 'ascii-character))
      (setq last-input-char (get last-input-char 'ascii-character)))
  (term-send-raw-string (make-string 1 last-input-char)))

(defun term-send-raw-meta ()
  (interactive)
  (if (symbolp last-input-char)
      ;; Convert `return' to C-m, etc.
      (let ((tmp (get last-input-char 'event-symbol-elements)))
	(if tmp
	    (setq last-input-char (car tmp)))
	(if (symbolp last-input-char)
	    (progn
	      (setq tmp (get last-input-char 'ascii-character))
	      (if tmp (setq last-input-char tmp))))))
  (term-send-raw-string (if (and (numberp last-input-char)
				 (> last-input-char 127)
				 (< last-input-char 256))
			    (make-string 1 last-input-char)
			  (format "\e%c" last-input-char))))

(defun term-mouse-paste (click arg)
  "Insert the last stretch of killed text at the position clicked on."
  (interactive "e\nP")
  (term-if-xemacs
   (term-send-raw-string (or (condition-case () (x-get-selection) (error ()))
			     (x-get-cutbuffer)
			     (error "No selection or cut buffer available"))))
  (term-ifnot-xemacs
   ;; Give temporary modes such as isearch a chance to turn off.
   (run-hooks 'mouse-leave-buffer-hook)
   (setq this-command 'yank)
   (term-send-raw-string (current-kill (cond
					((listp arg) 0)
					((eq arg '-) -1)
					(t (1- arg)))))))

;; Which would be better:  "\e[A" or "\eOA"? readline accepts either.
(defun term-send-up    () (interactive) (term-send-raw-string "\e[A"))
(defun term-send-down  () (interactive) (term-send-raw-string "\e[B"))
(defun term-send-right () (interactive) (term-send-raw-string "\e[C"))
(defun term-send-left  () (interactive) (term-send-raw-string "\e[D"))

(defun term-set-escape-char (c)
  "Change term-escape-char and keymaps that depend on it."
  (if term-escape-char
      (define-key term-raw-map term-escape-char 'term-send-raw))
  (setq c (make-string 1 c))
  (define-key term-raw-map c term-raw-escape-map)
  ;; Define standard bindings in term-raw-escape-map
  (define-key term-raw-escape-map "\C-x"
    (lookup-key (current-global-map) "\C-x"))
  (define-key term-raw-escape-map "\C-v"
    (lookup-key (current-global-map) "\C-v"))
  (define-key term-raw-escape-map "\C-u"
    (lookup-key (current-global-map) "\C-u"))
  (define-key term-raw-escape-map c 'term-send-raw)
  (define-key term-raw-escape-map "\C-q" 'term-pager-toggle)
  ;; The keybinding for term-char-mode is needed by the menubar code.
  (define-key term-raw-escape-map "\C-k" 'term-char-mode)
  (define-key term-raw-escape-map "\C-j" 'term-line-mode))
    
(defun term-char-mode ()
  "Switch to char (\"raw\") sub-mode of term mode.
Each character you type is sent directly to the inferior without
intervention from emacs, except for the escape character (usually C-c)."
  (interactive)
  (if (not term-raw-map)
      (let* ((map (make-keymap))
	     (esc-map (make-keymap))
	     (i 0))
	(while (< i 128)
	  (define-key map (make-string 1 i) 'term-send-raw)
	  (define-key esc-map (make-string 1 i) 'term-send-raw-meta)
	  (setq i (1+ i)))
	(define-key map "\e" esc-map)
	(setq term-raw-map map)
	(setq term-raw-escape-map
	      (copy-keymap (lookup-key (current-global-map) "\C-x")))
	(term-if-emacs19
	 (term-if-xemacs
	  (define-key term-raw-map [button2] 'term-mouse-paste))
	 (term-ifnot-xemacs
	  (define-key term-raw-map [mouse-2] 'term-mouse-paste)
	  (define-key term-raw-map [menu-bar terminal] term-terminal-menu)
	  (define-key term-raw-map [menu-bar signals] term-signals-menu))
	 (define-key term-raw-map [up] 'term-send-up)
	 (define-key term-raw-map [down] 'term-send-down)
	 (define-key term-raw-map [right] 'term-send-right)
	 (define-key term-raw-map [left] 'term-send-left))
	(term-set-escape-char ?\C-c)))
  ;; FIXME: Emit message? Cfr ilisp-raw-message
  (if (term-in-line-mode)
      (progn
	(setq term-old-mode-map (current-local-map))
	(use-local-map term-raw-map)

	;; Send existing partial line to inferior (without newline).
	(let ((pmark (process-mark (get-buffer-process (current-buffer))))
	      (save-input-sender term-input-sender))
	  (if (> (point) pmark)
	      (unwind-protect
		  (progn
		    (setq term-input-sender
			  (symbol-function 'term-send-string))
		    (end-of-line)
		    (term-send-input))
		(setq term-input-sender save-input-sender))))
	(term-update-mode-line))))

(defun term-line-mode  ()
  "Switch to line (\"cooked\") sub-mode of term mode.
This means that emacs editing commands work as normally, until
you type \\[term-send-input] which sends the current line to the inferior."
  (interactive)
  (if (term-in-char-mode)
      (progn
	(use-local-map term-old-mode-map)
	(term-update-mode-line))))

(defun term-update-mode-line ()
  (setq mode-line-process
	(if (term-in-char-mode)
	    (if (term-pager-enabled) '(": char page %s") '(": char %s"))
	  (if (term-pager-enabled) '(": line page %s") '(": line %s"))))
  (force-mode-line-update))

(defun term-check-proc (buffer)
  "True if there is a process associated w/buffer BUFFER, and
it is alive (status RUN or STOP). BUFFER can be either a buffer or the
name of one"
  (let ((proc (get-buffer-process buffer)))
    (and proc (memq (process-status proc) '(run stop)))))

;;; Note that this guy, unlike shell.el's make-shell, barfs if you pass it ()
;;; for the second argument (program).
;;;###autoload
(defun make-term (name program &optional startfile &rest switches)
"Make a term process NAME in a buffer, running PROGRAM.
The name of the buffer is made by surrounding NAME with `*'s.
If there is already a running process in that buffer, it is not restarted.
Optional third arg STARTFILE is the name of a file to send the contents of to 
the process.  Any more args are arguments to PROGRAM."
  (let ((buffer (get-buffer-create (concat "*" name "*"))))
    ;; If no process, or nuked process, crank up a new one and put buffer in
    ;; term mode. Otherwise, leave buffer and existing process alone.
    (cond ((not (term-check-proc buffer))
	   (save-excursion
	     (set-buffer buffer)
	     (term-mode)) ; Install local vars, mode, keymap, ...
	   (term-exec buffer name program startfile switches)))
    buffer))

;;;###autoload
(defun term (program)
  "Start a terminal-emulator in a new buffer."
  (interactive (list (read-from-minibuffer "Run program: "
					   (or explicit-shell-file-name
					       (getenv "ESHELL")
					       (getenv "SHELL")
					       "/bin/sh"))))
  (set-buffer (make-term "terminal" program))
  (term-mode)
  (term-char-mode)
  (switch-to-buffer "*terminal*"))

(defun term-exec (buffer name command startfile switches)
  "Start up a process in buffer for term modes.
Blasts any old process running in the buffer. Doesn't set the buffer mode.
You can use this to cheaply run a series of processes in the same term
buffer. The hook term-exec-hook is run after each exec."
  (save-excursion
    (set-buffer buffer)
    (let ((proc (get-buffer-process buffer)))	; Blast any old process.
      (if proc (delete-process proc)))
    ;; Crank up a new process
    (let ((proc (term-exec-1 name buffer command switches)))
      (make-local-variable 'term-ptyp)
      (setq term-ptyp process-connection-type) ; T if pty, NIL if pipe.
      ;; Jump to the end, and set the process mark.
      (goto-char (point-max))
      (set-marker (process-mark proc) (point))
      (set-process-filter proc 'term-emulate-terminal)
      ;; Feed it the startfile.
      (cond (startfile
	     ;;This is guaranteed to wait long enough
	     ;;but has bad results if the term does not prompt at all
	     ;;	     (while (= size (buffer-size))
	     ;;	       (sleep-for 1))
	     ;;I hope 1 second is enough!
	     (sleep-for 1)
	     (goto-char (point-max))
	     (insert-file-contents startfile)
	     (setq startfile (buffer-substring (point) (point-max)))
	     (delete-region (point) (point-max))
	     (term-send-string proc startfile)))
    (run-hooks 'term-exec-hook)
    buffer)))

;;; Name to use for TERM.
;;; Using "emacs" loses, because bash disables editing if TERM == emacs.
(defvar term-term-name "eterm")
; Format string, usage: (format term-termcap-string emacs-term-name "TERMCAP=" 24 80)
(defvar term-termcap-format
  "%s%s:li#%d:co#%d:cl=\\E[H\\E[J:cd=\\E[J:bs:am:xn:cm=\\E[%%i%%d;%%dH\
:nd=\\E[C:up=\\E[A:ce=\\E[K:ho=\\E[H:pt\
:al=\\E[L:dl=\\E[M:DL=\\E[%%dM:AL=\\E[%%dL:cs=\\E[%%i%%d;%%dr:sf=\\n\
:te=\\E[2J\\E[?47l\\E8:ti=\\E7\\E[?47h\
:dc=\\E[P:DC=\\E[%%dP:IC=\\E[%%d@:im=\\E[4h:ei=\\E[4l:mi:\
:so=\\E[7m:se=\\E[m:us=\\E[4m:ue=\\E[m:md=\\E[1m:mr=\\E[7m:me=\\E[m\
:UP=\\E[%%dA:DO=\\E[%%dB:LE=\\E[%%dD:RI=\\E[%%dC"
;;; : -undefine ic
  "termcap capabilities supported")

;;; This auxiliary function cranks up the process for term-exec in
;;; the appropriate environment.

(defun term-exec-1 (name buffer command switches)
  ;; We need to do an extra (fork-less) exec to run stty.
  ;; (This would not be needed if we had suitable emacs primitives.)
  ;; The 'if ...; then shift; fi' hack is because Bourne shell
  ;; loses one arg when called with -c, and newer shells (bash,  ksh) don't.
  ;; Thus we add an extra dummy argument "..", and then remove it.
  (let ((process-environment
	 (nconc
	  (list
	   (format "TERM=%s" term-term-name)
	   (if (and (boundp 'system-uses-terminfo) system-uses-terminfo)
	       (format "TERMINFO=%s" data-directory)
	    (format term-termcap-format "TERMCAP="
		    term-term-name term-height term-width))
	   (format "EMACS=%s (term:%s)" emacs-version term-protocol-version)
	   (format "LINES=%d" term-height)
	   (format "COLUMNS=%d" term-width))
	  process-environment))
	(process-connection-type t))
    (apply 'start-process name buffer
	   "/bin/sh" "-c"
	   (format "stty -nl echo rows %d columns %d sane 2>/dev/null;\
if [ $1 = .. ]; then shift; fi; exec \"$@\""
		   term-height term-width)
	   ".."
	   command switches)))

;;; This should be in emacs, but it isn't.
(defun term-mem (item list &optional elt=)
  "Test to see if ITEM is equal to an item in LIST.
Option comparison function ELT= defaults to equal."
  (let ((elt= (or elt= (function equal)))
	(done nil))
    (while (and list (not done))
      (if (funcall elt= item (car list))
	  (setq done list)
	  (setq list (cdr list))))
    done))


;;; Input history processing in a buffer
;;; ===========================================================================
;;; Useful input history functions, courtesy of the Ergo group.

;;; Eleven commands:
;;; term-dynamic-list-input-ring	List history in help buffer.
;;; term-previous-input		Previous input...
;;; term-previous-matching-input	...matching a string.
;;; term-previous-matching-input-from-input ... matching the current input.
;;; term-next-input			Next input...
;;; term-next-matching-input		...matching a string.
;;; term-next-matching-input-from-input     ... matching the current input.
;;; term-backward-matching-input      Backwards input...
;;; term-forward-matching-input       ...matching a string.
;;; term-replace-by-expanded-history	Expand history at point;
;;;					replace with expanded history.
;;; term-magic-space			Expand history and insert space.
;;;
;;; Three functions:
;;; term-read-input-ring              Read into term-input-ring...
;;; term-write-input-ring             Write to term-input-ring-file-name.
;;; term-replace-by-expanded-history-before-point Workhorse function.

(defun term-read-input-ring (&optional silent)
  "Sets the buffer's `term-input-ring' from a history file.
The name of the file is given by the variable `term-input-ring-file-name'.
The history ring is of size `term-input-ring-size', regardless of file size.
If `term-input-ring-file-name' is nil this function does nothing.

If the optional argument SILENT is non-nil, we say nothing about a
failure to read the history file.

This function is useful for major mode commands and mode hooks.

The structure of the history file should be one input command per line,
with the most recent command last.
See also `term-input-ignoredups' and `term-write-input-ring'."
  (cond ((or (null term-input-ring-file-name)
	     (equal term-input-ring-file-name ""))
	 nil)
	((not (file-readable-p term-input-ring-file-name))
	 (or silent
	     (message "Cannot read history file %s"
		      term-input-ring-file-name)))
	(t
	 (let ((history-buf (get-buffer-create " *temp*"))
	       (file term-input-ring-file-name)
	       (count 0)
	       (ring (make-ring term-input-ring-size)))
	   (unwind-protect
	       (save-excursion
		 (set-buffer history-buf)
		 (widen)
		 (erase-buffer)
		 (insert-file-contents file)
		 ;; Save restriction in case file is already visited...
		 ;; Watch for those date stamps in history files!
		 (goto-char (point-max))
		 (while (and (< count term-input-ring-size)
			     (re-search-backward "^[ \t]*\\([^#\n].*\\)[ \t]*$"
						 nil t))
		   (let ((history (buffer-substring (match-beginning 1)
						    (match-end 1))))
		     (if (or (null term-input-ignoredups)
			     (ring-empty-p ring)
			     (not (string-equal (ring-ref ring 0) history)))
			 (ring-insert-at-beginning ring history)))
		   (setq count (1+ count))))
	     (kill-buffer history-buf))
	   (setq term-input-ring ring
		 term-input-ring-index nil)))))

(defun term-write-input-ring ()
  "Writes the buffer's `term-input-ring' to a history file.
The name of the file is given by the variable `term-input-ring-file-name'.
The original contents of the file are lost if `term-input-ring' is not empty.
If `term-input-ring-file-name' is nil this function does nothing.

Useful within process sentinels.

See also `term-read-input-ring'."
  (cond ((or (null term-input-ring-file-name)
	     (equal term-input-ring-file-name "")
	     (null term-input-ring) (ring-empty-p term-input-ring))
	 nil)
	((not (file-writable-p term-input-ring-file-name))
	 (message "Cannot write history file %s" term-input-ring-file-name))
	(t
	 (let* ((history-buf (get-buffer-create " *Temp Input History*"))
		(ring term-input-ring)
		(file term-input-ring-file-name)
		(index (ring-length ring)))
	   ;; Write it all out into a buffer first.  Much faster, but messier,
	   ;; than writing it one line at a time.
	   (save-excursion
	     (set-buffer history-buf)
	     (erase-buffer)
	     (while (> index 0)
	       (setq index (1- index))
	       (insert (ring-ref ring index) ?\n))
	     (write-region (buffer-string) nil file nil 'no-message)
	     (kill-buffer nil))))))


(defun term-dynamic-list-input-ring ()
  "List in help buffer the buffer's input history."
  (interactive)
  (if (or (not (ring-p term-input-ring))
	  (ring-empty-p term-input-ring))
      (message "No history")
    (let ((history nil)
	  (history-buffer " *Input History*")
	  (index (1- (ring-length term-input-ring)))
	  (conf (current-window-configuration)))
      ;; We have to build up a list ourselves from the ring vector.
      (while (>= index 0)
	(setq history (cons (ring-ref term-input-ring index) history)
	      index (1- index)))
      ;; Change "completion" to "history reference"
      ;; to make the display accurate.
      (with-output-to-temp-buffer history-buffer
	(display-completion-list history)
	(set-buffer history-buffer)
	(forward-line 3)
	(while (search-backward "completion" nil 'move)
	  (replace-match "history reference")))
      (sit-for 0)
      (message "Hit space to flush")
      (let ((ch (read-event)))
	(if (eq ch ?\ )
	    (set-window-configuration conf)
	  (setq unread-command-events (list ch)))))))


(defun term-regexp-arg (prompt)
  ;; Return list of regexp and prefix arg using PROMPT.
  (let* ((minibuffer-history-sexp-flag nil)
	 ;; Don't clobber this.
	 (last-command last-command)
	 (regexp (read-from-minibuffer prompt nil nil nil
				       'minibuffer-history-search-history)))
    (list (if (string-equal regexp "")
	      (setcar minibuffer-history-search-history
		      (nth 1 minibuffer-history-search-history))
	    regexp)
	  (prefix-numeric-value current-prefix-arg))))

(defun term-search-arg (arg)
  ;; First make sure there is a ring and that we are after the process mark
  (cond ((not (term-after-pmark-p))
	 (error "Not at command line"))
	((or (null term-input-ring)
	     (ring-empty-p term-input-ring))
	 (error "Empty input ring"))
	((zerop arg)
	 ;; arg of zero resets search from beginning, and uses arg of 1
	 (setq term-input-ring-index nil)
	 1)
	(t
	 arg)))

(defun term-search-start (arg)
  ;; Index to start a directional search, starting at term-input-ring-index
  (if term-input-ring-index
      ;; If a search is running, offset by 1 in direction of arg
      (mod (+ term-input-ring-index (if (> arg 0) 1 -1))
	   (ring-length term-input-ring))
    ;; For a new search, start from beginning or end, as appropriate
    (if (>= arg 0)
	0				       ; First elt for forward search
      (1- (ring-length term-input-ring)))))  ; Last elt for backward search

(defun term-previous-input-string (arg)
  "Return the string ARG places along the input ring.
Moves relative to `term-input-ring-index'."
  (ring-ref term-input-ring (if term-input-ring-index
				  (mod (+ arg term-input-ring-index) 
				       (ring-length term-input-ring))
				arg)))

(defun term-previous-input (arg)
  "Cycle backwards through input history."
  (interactive "*p")
  (term-previous-matching-input "." arg))

(defun term-next-input (arg)
  "Cycle forwards through input history."
  (interactive "*p")
  (term-previous-input (- arg)))

(defun term-previous-matching-input-string (regexp arg)
  "Return the string matching REGEXP ARG places along the input ring.
Moves relative to `term-input-ring-index'."
  (let* ((pos (term-previous-matching-input-string-position regexp arg)))
    (if pos (ring-ref term-input-ring pos))))

(defun term-previous-matching-input-string-position (regexp arg &optional start)
  "Return the index matching REGEXP ARG places along the input ring.
Moves relative to START, or `term-input-ring-index'."
  (if (or (not (ring-p term-input-ring))
	  (ring-empty-p term-input-ring))
      (error "No history"))
  (let* ((len (ring-length term-input-ring))
	 (motion (if (> arg 0) 1 -1))
	 (n (mod (- (or start (term-search-start arg)) motion) len))
	 (tried-each-ring-item nil)
	 (prev nil))
    ;; Do the whole search as many times as the argument says.
    (while (and (/= arg 0) (not tried-each-ring-item))
      ;; Step once.
      (setq prev n
	    n (mod (+ n motion) len))
      ;; If we haven't reached a match, step some more.
      (while (and (< n len) (not tried-each-ring-item)
		  (not (string-match regexp (ring-ref term-input-ring n))))
	(setq n (mod (+ n motion) len)
	      ;; If we have gone all the way around in this search.
	      tried-each-ring-item (= n prev)))
      (setq arg (if (> arg 0) (1- arg) (1+ arg))))
    ;; Now that we know which ring element to use, if we found it, return that.
    (if (string-match regexp (ring-ref term-input-ring n))
	n)))

(defun term-previous-matching-input (regexp arg)
  "Search backwards through input history for match for REGEXP.
\(Previous history elements are earlier commands.)
With prefix argument N, search for Nth previous match.
If N is negative, find the next or Nth next match."
  (interactive (term-regexp-arg "Previous input matching (regexp): "))
  (setq arg (term-search-arg arg))
  (let ((pos (term-previous-matching-input-string-position regexp arg)))
    ;; Has a match been found?
    (if (null pos)
	(error "Not found")
      (setq term-input-ring-index pos)
      (message "History item: %d" (1+ pos))
      (delete-region 
       ;; Can't use kill-region as it sets this-command
       (process-mark (get-buffer-process (current-buffer))) (point))
      (insert (ring-ref term-input-ring pos)))))

(defun term-next-matching-input (regexp arg)
  "Search forwards through input history for match for REGEXP.
\(Later history elements are more recent commands.)
With prefix argument N, search for Nth following match.
If N is negative, find the previous or Nth previous match."
  (interactive (term-regexp-arg "Next input matching (regexp): "))
  (term-previous-matching-input regexp (- arg)))

(defun term-previous-matching-input-from-input (arg)
  "Search backwards through input history for match for current input.
\(Previous history elements are earlier commands.)
With prefix argument N, search for Nth previous match.
If N is negative, search forwards for the -Nth following match."
  (interactive "p")
  (if (not (memq last-command '(term-previous-matching-input-from-input
				term-next-matching-input-from-input)))
      ;; Starting a new search
      (setq term-matching-input-from-input-string
	    (buffer-substring 
	     (process-mark (get-buffer-process (current-buffer))) 
	     (point))
	    term-input-ring-index nil))
  (term-previous-matching-input
   (concat "^" (regexp-quote term-matching-input-from-input-string))
   arg))

(defun term-next-matching-input-from-input (arg)
  "Search forwards through input history for match for current input.
\(Following history elements are more recent commands.)
With prefix argument N, search for Nth following match.
If N is negative, search backwards for the -Nth previous match."
  (interactive "p")
  (term-previous-matching-input-from-input (- arg)))


(defun term-replace-by-expanded-history (&optional silent)
  "Expand input command history references before point.
Expansion is dependent on the value of `term-input-autoexpand'.

This function depends on the buffer's idea of the input history, which may not
match the command interpreter's idea, assuming it has one.

Assumes history syntax is like typical Un*x shells'.  However, since emacs
cannot know the interpreter's idea of input line numbers, assuming it has one,
it cannot expand absolute input line number references.

If the optional argument SILENT is non-nil, never complain
even if history reference seems erroneous.

See `term-magic-space' and `term-replace-by-expanded-history-before-point'.

Returns t if successful."
  (interactive)
  (if (and term-input-autoexpand
	   (string-match "[!^]" (funcall term-get-old-input))
	   (save-excursion (beginning-of-line)
			   (looking-at term-prompt-regexp)))
      ;; Looks like there might be history references in the command.
      (let ((previous-modified-tick (buffer-modified-tick)))
	(message "Expanding history references...")
	(term-replace-by-expanded-history-before-point silent)
	(/= previous-modified-tick (buffer-modified-tick)))))


(defun term-replace-by-expanded-history-before-point (silent)
  "Expand directory stack reference before point.
See `term-replace-by-expanded-history'.  Returns t if successful."
  (save-excursion
    (let ((toend (- (save-excursion (end-of-line nil) (point)) (point)))
	  (start (progn (term-bol nil) (point))))
      (while (progn
	       (skip-chars-forward "^!^"
				   (save-excursion
				     (end-of-line nil) (- (point) toend)))
	       (< (point)
		  (save-excursion
		    (end-of-line nil) (- (point) toend))))
	;; This seems a bit complex.  We look for references such as !!, !-num,
	;; !foo, !?foo, !{bar}, !?{bar}, ^oh, ^my^, ^god^it, ^never^ends^.
	;; If that wasn't enough, the plings can be suffixed with argument
	;; range specifiers.
	;; Argument ranges are complex too, so we hive off the input line,
	;; referenced with plings, with the range string to `term-args'.
	(setq term-input-ring-index nil)
	(cond ((or (= (preceding-char) ?\\)
		   (term-within-quotes start (point)))
	       ;; The history is quoted, or we're in quotes.
	       (goto-char (1+ (point))))
	      ((looking-at "![0-9]+\\($\\|[^-]\\)")
	       ;; We cannot know the interpreter's idea of input line numbers.
	       (goto-char (match-end 0))
	       (message "Absolute reference cannot be expanded"))
	      ((looking-at "!-\\([0-9]+\\)\\(:?[0-9^$*-]+\\)?")
	       ;; Just a number of args from `number' lines backward.
	       (let ((number (1- (string-to-number
				  (buffer-substring (match-beginning 1)
						    (match-end 1))))))
		 (if (<= number (ring-length term-input-ring))
		     (progn
		       (replace-match
			(term-args (term-previous-input-string number)
				     (match-beginning 2) (match-end 2))
			t t)
		       (setq term-input-ring-index number)
		       (message "History item: %d" (1+ number)))
		   (goto-char (match-end 0))
		   (message "Relative reference exceeds input history size"))))
	      ((or (looking-at "!!?:?\\([0-9^$*-]+\\)") (looking-at "!!"))
	       ;; Just a number of args from the previous input line.
	       (replace-match
		(term-args (term-previous-input-string 0)
			     (match-beginning 1) (match-end 1))
		t t)
	       (message "History item: previous"))
	      ((looking-at
		"!\\??\\({\\(.+\\)}\\|\\(\\sw+\\)\\)\\(:?[0-9^$*-]+\\)?")
	       ;; Most recent input starting with or containing (possibly
	       ;; protected) string, maybe just a number of args.  Phew.
	       (let* ((mb1 (match-beginning 1)) (me1 (match-end 1))
		      (mb2 (match-beginning 2)) (me2 (match-end 2))
		      (exp (buffer-substring (or mb2 mb1) (or me2 me1)))
		      (pref (if (save-match-data (looking-at "!\\?")) "" "^"))
		      (pos (save-match-data
			     (term-previous-matching-input-string-position
			      (concat pref (regexp-quote exp)) 1))))
		 (if (null pos)
		     (progn
		       (goto-char (match-end 0))
		       (or silent
			   (progn (message "Not found")
				  (ding))))
		   (setq term-input-ring-index pos)
		   (replace-match
		    (term-args (ring-ref term-input-ring pos)
				 (match-beginning 4) (match-end 4))
		    t t)
		   (message "History item: %d" (1+ pos)))))
	      ((looking-at "\\^\\([^^]+\\)\\^?\\([^^]*\\)\\^?")
	       ;; Quick substitution on the previous input line.
	       (let ((old (buffer-substring (match-beginning 1) (match-end 1)))
		     (new (buffer-substring (match-beginning 2) (match-end 2)))
		     (pos nil))
		 (replace-match (term-previous-input-string 0) t t)
		 (setq pos (point))
		 (goto-char (match-beginning 0))
		 (if (not (search-forward old pos t))
		     (or silent
			 (error "Not found"))
		   (replace-match new t t)
		   (message "History item: substituted"))))
	      (t
	       (goto-char (match-end 0))))))))


(defun term-magic-space (arg)
  "Expand input history references before point and insert ARG spaces.
A useful command to bind to SPC.  See `term-replace-by-expanded-history'."
  (interactive "p")
  (term-replace-by-expanded-history)
  (self-insert-command arg))

(defun term-within-quotes (beg end)
  "Return t if the number of quotes between BEG and END is odd.
Quotes are single and double."
  (let ((countsq (term-how-many-region "\\(^\\|[^\\\\]\\)\'" beg end))
	(countdq (term-how-many-region "\\(^\\|[^\\\\]\\)\"" beg end)))
    (or (= (mod countsq 2) 1) (= (mod countdq 2) 1))))

(defun term-how-many-region (regexp beg end)
  "Return number of matches for REGEXP from BEG to END."
  (let ((count 0))
    (save-excursion
      (save-match-data
	(goto-char beg)
	(while (re-search-forward regexp end t)
	  (setq count (1+ count)))))
    count))

(defun term-args (string begin end)
  ;; From STRING, return the args depending on the range specified in the text
  ;; from BEGIN to END.  If BEGIN is nil, assume all args.  Ignore leading `:'.
  ;; Range can be x-y, x-, -y, where x/y can be [0-9], *, ^, $.
  (save-match-data
    (if (null begin)
	(term-arguments string 0 nil)
      (let* ((range (buffer-substring
		     (if (eq (char-after begin) ?:) (1+ begin) begin) end))
	     (nth (cond ((string-match "^[*^]" range) 1)
			((string-match "^-" range) 0)
			((string-equal range "$") nil)
			(t (string-to-number range))))
	     (mth (cond ((string-match "[-*$]$" range) nil)
			((string-match "-" range)
			 (string-to-number (substring range (match-end 0))))
			(t nth))))
	(term-arguments string nth mth)))))

;; Return a list of arguments from ARG.  Break it up at the
;; delimiters in term-delimiter-argument-list.  Returned list is backwards.
(defun term-delim-arg (arg)
  (if (null term-delimiter-argument-list)
      (list arg)
    (let ((args nil)
	  (pos 0)
	  (len (length arg)))
      (while (< pos len)
	(let ((char (aref arg pos))
	      (start pos))
	  (if (memq char term-delimiter-argument-list)
	      (while (and (< pos len) (eq (aref arg pos) char))
		(setq pos (1+ pos)))
	    (while (and (< pos len)
			(not (memq (aref arg pos)
				   term-delimiter-argument-list)))
	      (setq pos (1+ pos))))
	  (setq args (cons (substring arg start pos) args))))
      args)))

(defun term-arguments (string nth mth)
  "Return from STRING the NTH to MTH arguments.
NTH and/or MTH can be nil, which means the last argument.
Returned arguments are separated by single spaces.
We assume whitespace separates arguments, except within quotes.
Also, a run of one or more of a single character
in `term-delimiter-argument-list' is a separate argument.
Argument 0 is the command name."
  (let ((argpart "[^ \n\t\"'`]+\\|\\(\"[^\"]*\"\\|'[^']*'\\|`[^`]*`\\)")
	(args ()) (pos 0)
	(count 0)
	beg str quotes)
    ;; Build a list of all the args until we have as many as we want.
    (while (and (or (null mth) (<= count mth))
		(string-match argpart string pos))
      (if (and beg (= pos (match-beginning 0)))
	  ;; It's contiguous, part of the same arg.
	  (setq pos (match-end 0)
		quotes (or quotes (match-beginning 1)))
	;; It's a new separate arg.
	(if beg
	    ;; Put the previous arg, if there was one, onto ARGS.
	    (setq str (substring string beg pos)
		  args (if quotes (cons str args)
			 (nconc (term-delim-arg str) args))
		  count (1+ count)))
	(setq quotes (match-beginning 1))
	(setq beg (match-beginning 0))
	(setq pos (match-end 0))))
    (if beg
	(setq str (substring string beg pos)
	      args (if quotes (cons str args)
		     (nconc (term-delim-arg str) args))
	      count (1+ count)))
    (let ((n (or nth (1- count)))
	  (m (if mth (1- (- count mth)) 0)))
      (mapconcat
       (function (lambda (a) a)) (nthcdr n (nreverse (nthcdr m args))) " "))))

;;;
;;; Input processing stuff [line mode]
;;;

(defun term-send-input () 
  "Send input to process.
After the process output mark, sends all text from the process mark to
point as input to the process.  Before the process output mark, calls value
of variable term-get-old-input to retrieve old input, copies it to the
process mark, and sends it.  A terminal newline is also inserted into the
buffer and sent to the process.  The list of function names contained in the
value of `term-input-filter-functions' is called on the input before sending
it.  The input is entered into the input history ring, if the value of variable
term-input-filter returns non-nil when called on the input.

Any history reference may be expanded depending on the value of the variable
`term-input-autoexpand'.  The list of function names contained in the value
of `term-input-filter-functions' is called on the input before sending it.
The input is entered into the input history ring, if the value of variable
`term-input-filter' returns non-nil when called on the input.

If variable `term-eol-on-send' is non-nil, then point is moved to the
end of line before sending the input.

The values of `term-get-old-input', `term-input-filter-functions', and
`term-input-filter' are chosen according to the command interpreter running
in the buffer.  E.g.,

If the interpreter is the csh,
    term-get-old-input is the default: take the current line, discard any
        initial string matching regexp term-prompt-regexp.
    term-input-filter-functions monitors input for \"cd\", \"pushd\", and
	\"popd\" commands. When it sees one, it cd's the buffer.
    term-input-filter is the default: returns T if the input isn't all white
	space.

If the term is Lucid Common Lisp, 
    term-get-old-input snarfs the sexp ending at point.
    term-input-filter-functions does nothing.
    term-input-filter returns NIL if the input matches input-filter-regexp,
        which matches (1) all whitespace (2) :a, :c, etc.

Similarly for Soar, Scheme, etc."
  (interactive)
  ;; Note that the input string does not include its terminal newline.
  (let ((proc (get-buffer-process (current-buffer))))
    (if (not proc) (error "Current buffer has no process")
      (let* ((pmark (process-mark proc))
	     (pmark-val (marker-position pmark))
	     (input-is-new (>= (point) pmark-val))
	     (intxt (if input-is-new
			(progn (if term-eol-on-send (end-of-line))
			       (buffer-substring pmark (point)))
		      (funcall term-get-old-input)))
	     (input (if (not (eq term-input-autoexpand 'input))
			;; Just whatever's already there
			intxt
		      ;; Expand and leave it visible in buffer
		      (term-replace-by-expanded-history t)
		      (buffer-substring pmark (point))))
	     (history (if (not (eq term-input-autoexpand 'history))
			  input
			;; This is messy 'cos ultimately the original
			;; functions used do insertion, rather than return
			;; strings.  We have to expand, then insert back.
			(term-replace-by-expanded-history t)
			(let ((copy (buffer-substring pmark (point))))
			  (delete-region pmark (point))
			  (insert input)
			  copy))))
	(if (term-pager-enabled)
	    (save-excursion
	      (goto-char (process-mark proc))
	      (setq term-pager-count (term-current-row))))
	(if (and (funcall term-input-filter history)
		 (or (null term-input-ignoredups)
		     (not (ring-p term-input-ring))
		     (ring-empty-p term-input-ring)
		     (not (string-equal (ring-ref term-input-ring 0)
					history))))
	    (ring-insert term-input-ring history))
	(let ((functions term-input-filter-functions))
	  (while functions
	    (funcall (car functions) (concat input "\n"))
	    (setq functions (cdr functions))))
	(setq term-input-ring-index nil)

	;; Update the markers before we send the input
	;; in case we get output amidst sending the input.
	(set-marker term-last-input-start pmark)
	(set-marker term-last-input-end (point))
	(if input-is-new
	    (progn
	      ;; Set up to delete, because inferior should echo.
	      (if (marker-buffer term-pending-delete-marker)
		  (delete-region term-pending-delete-marker pmark))
	      (set-marker term-pending-delete-marker pmark-val)
	      (set-marker (process-mark proc) (point))))
	(goto-char pmark)
	(funcall term-input-sender proc input)))))

(defun term-get-old-input-default ()
  "Default for term-get-old-input.
Take the current line, and discard any initial text matching
term-prompt-regexp."
  (save-excursion
    (beginning-of-line)
    (term-skip-prompt)
    (let ((beg (point)))
      (end-of-line)
      (buffer-substring beg (point)))))

(defun term-copy-old-input ()
  "Insert after prompt old input at point as new input to be edited.
Calls `term-get-old-input' to get old input."
  (interactive)
  (let ((input (funcall term-get-old-input))
 	(process (get-buffer-process (current-buffer))))
    (if (not process)
	(error "Current buffer has no process")
      (goto-char (process-mark process))
      (insert input))))

(defun term-skip-prompt ()
  "Skip past the text matching regexp term-prompt-regexp. 
If this takes us past the end of the current line, don't skip at all."
  (let ((eol (save-excursion (end-of-line) (point))))
    (if (and (looking-at term-prompt-regexp)
	     (<= (match-end 0) eol))
	(goto-char (match-end 0)))))


(defun term-after-pmark-p ()
  "Is point after the process output marker?"
  ;; Since output could come into the buffer after we looked at the point
  ;; but before we looked at the process marker's value, we explicitly 
  ;; serialise. This is just because I don't know whether or not emacs
  ;; services input during execution of lisp commands.
  (let ((proc-pos (marker-position
		   (process-mark (get-buffer-process (current-buffer))))))
    (<= proc-pos (point))))

(defun term-simple-send (proc string)
  "Default function for sending to PROC input STRING.
This just sends STRING plus a newline. To override this,
set the hook TERM-INPUT-SENDER."
  (term-send-string proc string)
  (term-send-string proc "\n"))

(defun term-bol (arg)
  "Goes to the beginning of line, then skips past the prompt, if any.
If a prefix argument is given (\\[universal-argument]), then no prompt skip 
-- go straight to column 0.

The prompt skip is done by skipping text matching the regular expression
term-prompt-regexp, a buffer local variable."
  (interactive "P")
  (beginning-of-line)
  (if (null arg) (term-skip-prompt)))

;;; These two functions are for entering text you don't want echoed or
;;; saved -- typically passwords to ftp, telnet, or somesuch.
;;; Just enter m-x term-send-invisible and type in your line.

(defun term-read-noecho (prompt &optional stars)
  "Read a single line of text from user without echoing, and return it. 
Prompt with argument PROMPT, a string.  Optional argument STARS causes
input to be echoed with '*' characters on the prompt line.  Input ends with
RET, LFD, or ESC.  DEL or C-h rubs out.  C-u kills line.  C-g aborts (if
`inhibit-quit' is set because e.g. this function was called from a process
filter and C-g is pressed, this function returns nil rather than a string).

Note that the keystrokes comprising the text can still be recovered
\(temporarily) with \\[view-lossage].  This may be a security bug for some
applications."
  (let ((ans "")
	(c 0)
	(echo-keystrokes 0)
	(cursor-in-echo-area t)
        (done nil))
    (while (not done)
      (if stars
          (message "%s%s" prompt (make-string (length ans) ?*))
        (message "%s" prompt))
      (setq c (read-char))
      (cond ((= c ?\C-g)
             ;; This function may get called from a process filter, where
             ;; inhibit-quit is set.  In later versions of emacs read-char
             ;; may clear quit-flag itself and return C-g.  That would make
             ;; it impossible to quit this loop in a simple way, so
             ;; re-enable it here (for backward-compatibility the check for
             ;; quit-flag below would still be necessary, so this seems
             ;; like the simplest way to do things).
             (setq quit-flag t
                   done t))
            ((or (= c ?\r) (= c ?\n) (= c ?\e))
             (setq done t))
            ((= c ?\C-u)
             (setq ans ""))
            ((and (/= c ?\b) (/= c ?\177))
             (setq ans (concat ans (char-to-string c))))
            ((> (length ans) 0)
             (setq ans (substring ans 0 -1)))))
    (if quit-flag
        ;; Emulate a true quit, except that we have to return a value.
        (prog1
            (setq quit-flag nil)
          (message "Quit")
          (beep t))
      (message "")
      ans)))

(defun term-send-invisible (str &optional proc)
  "Read a string without echoing.
Then send it to the process running in the current buffer. A new-line
is additionally sent. String is not saved on term input history list.
Security bug: your string can still be temporarily recovered with
\\[view-lossage]."
  (interactive "P") ; Defeat snooping via C-x esc
  (if (not (stringp str))
      (setq str (term-read-noecho "Non-echoed text: " t)))
  (if (not proc)
      (setq proc (get-buffer-process (current-buffer))))
  (if (not proc) (error "Current buffer has no process")
    (setq term-kill-echo-list (nconc term-kill-echo-list
				     (cons str nil)))
    (term-send-string proc str)
    (term-send-string proc "\n")))


;;; Low-level process communication

(defvar term-input-chunk-size 512
  "*Long inputs send to term processes are broken up into chunks of this size.
If your process is choking on big inputs, try lowering the value.")

(defun term-send-string (proc str)
  "Send PROCESS the contents of STRING as input.
This is equivalent to process-send-string, except that long input strings
are broken up into chunks of size term-input-chunk-size. Processes
are given a chance to output between chunks. This can help prevent processes
from hanging when you send them long inputs on some OS's."
  (let* ((len (length str))
	 (i (min len term-input-chunk-size)))
    (process-send-string proc (substring str 0 i))
    (while (< i len)
      (let ((next-i (+ i term-input-chunk-size)))
	(accept-process-output)
	(process-send-string proc (substring str i (min len next-i)))
	(setq i next-i)))))

(defun term-send-region (proc start end)
  "Sends to PROC the region delimited by START and END.
This is a replacement for process-send-region that tries to keep
your process from hanging on long inputs. See term-send-string."
  (term-send-string proc (buffer-substring start end)))


;;; Random input hackage

(defun term-kill-output ()
  "Kill all output from interpreter since last input."
  (interactive)
  (let ((pmark (process-mark (get-buffer-process (current-buffer)))))
    (kill-region term-last-input-end pmark)
    (goto-char pmark)    
    (insert "*** output flushed ***\n")
    (set-marker pmark (point))))

(defun term-show-output ()
  "Display start of this batch of interpreter output at top of window.
Sets mark to the value of point when this command is run."
  (interactive)
  (goto-char term-last-input-end)
  (backward-char)
  (beginning-of-line)
  (set-window-start (selected-window) (point))
  (end-of-line))

(defun term-interrupt-subjob ()
  "Interrupt the current subjob."
  (interactive)
  (interrupt-process nil term-ptyp))

(defun term-kill-subjob ()
  "Send kill signal to the current subjob."
  (interactive)
  (kill-process nil term-ptyp))

(defun term-quit-subjob ()
  "Send quit signal to the current subjob."
  (interactive)
  (quit-process nil term-ptyp))

(defun term-stop-subjob ()
  "Stop the current subjob.
WARNING: if there is no current subjob, you can end up suspending
the top-level process running in the buffer. If you accidentally do
this, use \\[term-continue-subjob] to resume the process. (This
is not a problem with most shells, since they ignore this signal.)"
  (interactive)
  (stop-process nil term-ptyp))

(defun term-continue-subjob ()
  "Send CONT signal to process buffer's process group.
Useful if you accidentally suspend the top-level process."
  (interactive)
  (continue-process nil term-ptyp))

(defun term-kill-input ()
  "Kill all text from last stuff output by interpreter to point."
  (interactive)
  (let* ((pmark (process-mark (get-buffer-process (current-buffer))))
	 (p-pos (marker-position pmark)))
    (if (> (point) p-pos)
	(kill-region pmark (point)))))

(defun term-delchar-or-maybe-eof (arg)
  "Delete ARG characters forward, or send an EOF to process if at end of buffer."
  (interactive "p")
  (if (eobp)
      (process-send-eof)
      (delete-char arg)))

(defun term-send-eof ()
  "Send an EOF to the current buffer's process."
  (interactive)
  (process-send-eof))

(defun term-backward-matching-input (regexp arg)
  "Search backward through buffer for match for REGEXP.
Matches are searched for on lines that match `term-prompt-regexp'.
With prefix argument N, search for Nth previous match.
If N is negative, find the next or Nth next match."
  (interactive (term-regexp-arg "Backward input matching (regexp): "))
  (let* ((re (concat term-prompt-regexp ".*" regexp))
	 (pos (save-excursion (end-of-line (if (> arg 0) 0 1))
			      (if (re-search-backward re nil t arg)
				  (point)))))
    (if (null pos)
	(progn (message "Not found")
	       (ding))
      (goto-char pos)
      (term-bol nil))))

(defun term-forward-matching-input (regexp arg)
  "Search forward through buffer for match for REGEXP.
Matches are searched for on lines that match `term-prompt-regexp'.
With prefix argument N, search for Nth following match.
If N is negative, find the previous or Nth previous match."
  (interactive (term-regexp-arg "Forward input matching (regexp): "))
  (term-backward-matching-input regexp (- arg)))


(defun term-next-prompt (n)
  "Move to end of Nth next prompt in the buffer.
See `term-prompt-regexp'."
  (interactive "p")
  (let ((paragraph-start term-prompt-regexp))
    (end-of-line (if (> n 0) 1 0))
    (forward-paragraph n)
    (term-skip-prompt)))

(defun term-previous-prompt (n)
  "Move to end of Nth previous prompt in the buffer.
See `term-prompt-regexp'."
  (interactive "p")
  (term-next-prompt (- n)))

;;; Support for source-file processing commands.
;;;============================================================================
;;; Many command-interpreters (e.g., Lisp, Scheme, Soar) have
;;; commands that process files of source text (e.g. loading or compiling
;;; files). So the corresponding process-in-a-buffer modes have commands
;;; for doing this (e.g., lisp-load-file). The functions below are useful
;;; for defining these commands.
;;;
;;; Alas, these guys don't do exactly the right thing for Lisp, Scheme
;;; and Soar, in that they don't know anything about file extensions.
;;; So the compile/load interface gets the wrong default occasionally.
;;; The load-file/compile-file default mechanism could be smarter -- it
;;; doesn't know about the relationship between filename extensions and
;;; whether the file is source or executable. If you compile foo.lisp
;;; with compile-file, then the next load-file should use foo.bin for
;;; the default, not foo.lisp. This is tricky to do right, particularly
;;; because the extension for executable files varies so much (.o, .bin,
;;; .lbin, .mo, .vo, .ao, ...).


;;; TERM-SOURCE-DEFAULT -- determines defaults for source-file processing
;;; commands.
;;;
;;; TERM-CHECK-SOURCE -- if FNAME is in a modified buffer, asks you if you
;;; want to save the buffer before issuing any process requests to the command
;;; interpreter.
;;;
;;; TERM-GET-SOURCE -- used by the source-file processing commands to prompt
;;; for the file to process.

;;; (TERM-SOURCE-DEFAULT previous-dir/file source-modes)
;;;============================================================================
;;; This function computes the defaults for the load-file and compile-file
;;; commands for tea, soar, cmulisp, and cmuscheme modes. 
;;; 
;;; - PREVIOUS-DIR/FILE is a pair (directory . filename) from the last 
;;; source-file processing command. NIL if there hasn't been one yet.
;;; - SOURCE-MODES is a list used to determine what buffers contain source
;;; files: if the major mode of the buffer is in SOURCE-MODES, it's source.
;;; Typically, (lisp-mode) or (scheme-mode).
;;; 
;;; If the command is given while the cursor is inside a string, *and*
;;; the string is an existing filename, *and* the filename is not a directory,
;;; then the string is taken as default. This allows you to just position
;;; your cursor over a string that's a filename and have it taken as default.
;;;
;;; If the command is given in a file buffer whose major mode is in
;;; SOURCE-MODES, then the the filename is the default file, and the
;;; file's directory is the default directory.
;;; 
;;; If the buffer isn't a source file buffer (e.g., it's the process buffer),
;;; then the default directory & file are what was used in the last source-file
;;; processing command (i.e., PREVIOUS-DIR/FILE).  If this is the first time
;;; the command has been run (PREVIOUS-DIR/FILE is nil), the default directory
;;; is the cwd, with no default file. (\"no default file\" = nil)
;;; 
;;; SOURCE-REGEXP is typically going to be something like (tea-mode)
;;; for T programs, (lisp-mode) for Lisp programs, (soar-mode lisp-mode)
;;; for Soar programs, etc.
;;; 
;;; The function returns a pair: (default-directory . default-file).

(defun term-source-default (previous-dir/file source-modes)
  (cond ((and buffer-file-name (memq major-mode source-modes))
	 (cons (file-name-directory    buffer-file-name)
	       (file-name-nondirectory buffer-file-name)))
	(previous-dir/file)
	(t
	 (cons default-directory nil))))


;;; (TERM-CHECK-SOURCE fname)
;;;============================================================================
;;; Prior to loading or compiling (or otherwise processing) a file (in the CMU
;;; process-in-a-buffer modes), this function can be called on the filename.
;;; If the file is loaded into a buffer, and the buffer is modified, the user
;;; is queried to see if he wants to save the buffer before proceeding with
;;; the load or compile.

(defun term-check-source (fname)
  (let ((buff (get-file-buffer fname)))
    (if (and buff
	     (buffer-modified-p buff)
	     (y-or-n-p (format "Save buffer %s first? "
			       (buffer-name buff))))
	;; save BUFF.
	(let ((old-buffer (current-buffer)))
	  (set-buffer buff)
	  (save-buffer)
	  (set-buffer old-buffer)))))


;;; (TERM-GET-SOURCE prompt prev-dir/file source-modes mustmatch-p)
;;;============================================================================
;;; TERM-GET-SOURCE is used to prompt for filenames in command-interpreter
;;; commands that process source files (like loading or compiling a file).
;;; It prompts for the filename, provides a default, if there is one,
;;; and returns the result filename.
;;; 
;;; See TERM-SOURCE-DEFAULT for more on determining defaults.
;;; 
;;; PROMPT is the prompt string. PREV-DIR/FILE is the (directory . file) pair
;;; from the last source processing command.  SOURCE-MODES is a list of major
;;; modes used to determine what file buffers contain source files.  (These
;;; two arguments are used for determining defaults). If MUSTMATCH-P is true,
;;; then the filename reader will only accept a file that exists.
;;; 
;;; A typical use:
;;; (interactive (term-get-source "Compile file: " prev-lisp-dir/file
;;;                                 '(lisp-mode) t))

;;; This is pretty stupid about strings. It decides we're in a string
;;; if there's a quote on both sides of point on the current line.
(defun term-extract-string ()
  "Returns string around POINT that starts the current line or nil." 
  (save-excursion
    (let* ((point (point))
	   (bol (progn (beginning-of-line) (point)))
	   (eol (progn (end-of-line) (point)))
	   (start (progn (goto-char point) 
			 (and (search-backward "\"" bol t) 
			      (1+ (point)))))
	   (end (progn (goto-char point)
		       (and (search-forward "\"" eol t)
			    (1- (point))))))
      (and start end
	   (buffer-substring start end)))))

(defun term-get-source (prompt prev-dir/file source-modes mustmatch-p)
  (let* ((def (term-source-default prev-dir/file source-modes))
         (stringfile (term-extract-string))
	 (sfile-p (and stringfile
		       (condition-case ()
			   (file-exists-p stringfile)
			 (error nil))
		       (not (file-directory-p stringfile))))
	 (defdir  (if sfile-p (file-name-directory stringfile)
                      (car def)))
	 (deffile (if sfile-p (file-name-nondirectory stringfile)
                      (cdr def)))
	 (ans (read-file-name (if deffile (format "%s(default %s) "
						  prompt    deffile)
				  prompt)
			      defdir
			      (concat defdir deffile)
			      mustmatch-p)))
    (list (expand-file-name (substitute-in-file-name ans)))))

;;; I am somewhat divided on this string-default feature. It seems
;;; to violate the principle-of-least-astonishment, in that it makes
;;; the default harder to predict, so you actually have to look and see
;;; what the default really is before choosing it. This can trip you up.
;;; On the other hand, it can be useful, I guess. I would appreciate feedback
;;; on this.
;;;     -Olin


;;; Simple process query facility.
;;; ===========================================================================
;;; This function is for commands that want to send a query to the process
;;; and show the response to the user. For example, a command to get the
;;; arglist for a Common Lisp function might send a "(arglist 'foo)" query
;;; to an inferior Common Lisp process.
;;; 
;;; This simple facility just sends strings to the inferior process and pops
;;; up a window for the process buffer so you can see what the process
;;; responds with.  We don't do anything fancy like try to intercept what the
;;; process responds with and put it in a pop-up window or on the message
;;; line. We just display the buffer. Low tech. Simple. Works good.

;;; Send to the inferior process PROC the string STR. Pop-up but do not select
;;; a window for the inferior process so that its response can be seen.
(defun term-proc-query (proc str)
  (let* ((proc-buf (process-buffer proc))
	 (proc-mark (process-mark proc)))
    (display-buffer proc-buf)
    (set-buffer proc-buf) ; but it's not the selected *window*
    (let ((proc-win (get-buffer-window proc-buf))
	  (proc-pt (marker-position proc-mark)))
      (term-send-string proc str) ; send the query
      (accept-process-output proc)  ; wait for some output
      ;; Try to position the proc window so you can see the answer.
      ;; This is bogus code. If you delete the (sit-for 0), it breaks.
      ;; I don't know why. Wizards invited to improve it.
      (if (not (pos-visible-in-window-p proc-pt proc-win))
	  (let ((opoint (window-point proc-win)))
	    (set-window-point proc-win proc-mark) (sit-for 0)
	    (if (not (pos-visible-in-window-p opoint proc-win))
		(push-mark opoint)
		(set-window-point proc-win opoint)))))))

;;; Returns the current column in the current screen line.
;;; Note: (current-column) yields column in buffer line.

(defun term-horizontal-column ()
  (- (term-current-column) (term-start-line-column)))

;; Calls either vertical-motion or buffer-vertical-motion
(defmacro term-vertical-motion (count)
  (list 'funcall 'term-vertical-motion count))

;; An emulation of vertical-motion that is independent of having a window.
;; Instead, it uses the term-width variable as the logical window width.

(defun buffer-vertical-motion (count)
  (cond ((= count 0)
	 (move-to-column (* term-width (/ (current-column) term-width)))
	 0)
	((> count 0)
	 (let ((H)
	       (todo (+ count (/ (current-column) term-width))))
	   (end-of-line)
	   ;; The loop iterates over buffer lines;
	   ;; H is the number of screen lines in the current line, i.e.
	   ;; the ceiling of dividing the buffer line width by term-width.
	   (while (and (<= (setq H (max (/ (+ (current-column) term-width -1)
					   term-width)
					1))
			   todo)
		       (not (eobp)))
	     (setq todo (- todo H))
	     (forward-char) ;; Move past the ?\n
	     (end-of-line)) ;; and on to the end of the next line.
	   (if (and (>= todo H) (> todo 0))
	       (+ (- count todo) H -1) ;; Hit end of buffer.
	     (move-to-column (* todo term-width))
	     count)))
	(t ;; (< count 0) ;; Similar algorithm, but for upward motion.
	 (let ((H)
	       (todo (- count)))
	   (while (and (<= (setq H (max (/ (+ (current-column) term-width -1)
					   term-width)
					1))
			   todo)
		       (progn (beginning-of-line)
			      (not (bobp))))
	     (setq todo (- todo H))
	     (backward-char)) ;; Move to end of previous line.
	   (if (and (>= todo H) (> todo 0))
	       (+ count todo (- 1 H)) ;; Hit beginning of buffer.
	     (move-to-column (* (- H todo 1) term-width))
	     count)))))

;;; The term-start-line-column variable is used as a cache.
(defun term-start-line-column ()
  (cond (term-start-line-column)
	((let ((save-pos (point)))
	   (term-vertical-motion 0)
	   (setq term-start-line-column (current-column))
	   (goto-char save-pos)
	   term-start-line-column))))

;;; Same as (current-column), but uses term-current-column as a cache.
(defun term-current-column ()
  (cond (term-current-column)
	((setq term-current-column (current-column)))))

;;; Move DELTA column right (or left if delta < 0).

(defun term-move-columns (delta)
  (setq term-current-column (+ (term-current-column) delta))
  (move-to-column term-current-column t))

;; Insert COUNT copies of CHAR in the default face.
(defun term-insert-char (char count)
  (let ((old-point (point)))
    (insert-char char count)
    (put-text-property old-point (point) 'face 'default)))

(defun term-current-row ()
  (cond (term-current-row)
	((setq term-current-row
	       (save-restriction
		 (save-excursion
		   (narrow-to-region term-home-marker (point-max))
		   (- (term-vertical-motion -9999))))))))

(defun term-adjust-current-row-cache (delta)
  (if term-current-row
      (setq term-current-row (+ term-current-row delta))))

(defun term-terminal-pos ()
  (save-excursion ;    save-restriction
    (let ((save-col (term-current-column))
	  x y)
      (term-vertical-motion 0)
      (setq x (- save-col (current-column)))
      (setq y (term-vertical-motion term-height))
      (cons x y))))

;;; Terminal emulation
;;; This is the standard process filter for term buffers.
;;; It emulates (most of the features of) a VT100/ANSI-style terminal.

(defun term-emulate-terminal (proc str)
  (let* ((previous-buffer (current-buffer))
	 (i 0) char funny count save-point save-marker old-point temp win
	 (selected (selected-window))
	 (str-length (length str)))
    (unwind-protect
	(progn
	  (set-buffer (process-buffer proc))

	  (if (marker-buffer term-pending-delete-marker)
	      (progn
		;; Delete text following term-pending-delete-marker.
		(delete-region term-pending-delete-marker (process-mark proc))
		(set-marker term-pending-delete-marker nil)))

	  (if (eq (window-buffer) (current-buffer))
	      (progn
		(setq term-vertical-motion (symbol-function 'vertical-motion))
		(term-check-size proc))
	    (setq term-vertical-motion
		  (symbol-function 'buffer-vertical-motion)))

	  (setq save-marker (copy-marker (process-mark proc)))

	  (if (/= (point) (process-mark proc))
	      (progn (setq save-point (point-marker))
		     (goto-char (process-mark proc))))

	  (save-restriction
	    ;; If the buffer is in line mode, and there is a partial
	    ;; input line, save the line (by narrowing to leave it
	    ;; outside the restriction ) until we're done with output.
	    (if (and (> (point-max) (process-mark proc))
		     (term-in-line-mode))
		(narrow-to-region (point-min) (process-mark proc)))
	    
	    (if term-log-buffer
		(princ str term-log-buffer))
	    (cond ((eq term-terminal-state 4) ;; Have saved pending output.
		   (setq str (concat term-terminal-parameter str))
		   (setq term-terminal-parameter nil)
		   (setq str-length (length str))
		   (setq term-terminal-state 0)))
	    
	    (while (< i str-length)
	      (setq char (aref str i))
	      (cond ((< term-terminal-state 2)
		     ;; Look for prefix of regular chars
		     (setq funny
			   (string-match "[\r\n\000\007\033\t\b\032\016\017]"
					 str i))
		     (if (not funny) (setq funny str-length))
		     (cond ((> funny i)
			    (cond ((eq term-terminal-state 1)
				   (term-move-columns 1)
				   (setq term-terminal-state 0)))
			    (setq count (- funny i))
			    (setq temp (- (+ (term-horizontal-column) count)
					  term-width))
			    (cond ((<= temp 0)) ;; All count chars fit in line.
				  ((> count temp) ;; Some chars fit.
				   ;; This iteration, handle only what fits.
				   (setq count (- count temp))
				   (setq funny (+ count i)))
				  ((or (not (or term-pager-count
						term-scroll-with-delete))
				       (>  (term-handle-scroll 1) 0))
				   (term-adjust-current-row-cache 1)
				   (setq count (min count term-width))
				   (setq funny (+ count i))
				   (setq term-start-line-column
					 term-current-column))
				  (t ;; Doing PAGER processing.
				   (setq count 0 funny i)
				   (setq term-current-column nil)
				   (setq term-start-line-column nil)))
			    (setq old-point (point))
			    ;; In the common case that we're at the end of
			    ;; the buffer, we can save a little work.
			    (cond ((/= (point) (point-max))
				   (if term-insert-mode
				       ;; Inserting spaces, then deleting them,
				       ;; then inserting the actual text is
				       ;; inefficient, but it is simple, and
				       ;; the actual overhead is miniscule.
				       (term-insert-spaces count))
				   (term-move-columns count)
				   (delete-region old-point (point)))
	(t (setq term-current-column (+ (term-current-column) count))))
			    (insert (substring str i funny))
			    (put-text-property old-point (point)
					       'face term-current-face)
			    ;; If the last char was written in last column,
			    ;; back up one column, but remember we did so.
			    ;; Thus we emulate xterm/vt100-style line-wrapping.
			    (cond ((eq temp 0)
				   (term-move-columns -1)
				   (setq term-terminal-state 1)))
			    (setq i (1- funny)))
			   ((and (setq term-terminal-state 0)
			    (eq char ?\^I)) ; TAB
			    ;; FIXME:  Does not handle line wrap!
			    (setq count (term-current-column))
			    (setq count (+ count 8 (- (mod count 8))))
			    (if (< (move-to-column count nil) count)
				(term-insert-char char 1))
			    (setq term-current-column count))
			   ((eq char ?\r)
			    ;; Optimize CRLF at end of buffer:
			    (cond ((and (< (setq temp (1+ i)) str-length)
					(eq (aref str temp) ?\n)
					(= (point) (point-max))
					(not (or term-pager-count
						 term-kill-echo-list
						 term-scroll-with-delete)))
				   (insert ?\n)
				   (term-adjust-current-row-cache 1)
				   (setq term-start-line-column 0)
				   (setq term-current-column 0)
				   (setq i temp))
				  (t ;; Not followed by LF or can't optimize:
				   (term-vertical-motion 0)
				   (setq term-current-column term-start-line-column))))
			   ((eq char ?\n)
			    (if (not (and term-kill-echo-list
					  (term-check-kill-echo-list)))
				(term-down 1 t)))
			   ((eq char ?\b)
			    (term-move-columns -1))
			   ((eq char ?\033) ; Escape
			    (setq term-terminal-state 2))
			   ((eq char 0)) ; NUL: Do nothing
			   ((eq char ?\016)) ; Shift Out - ignored
			   ((eq char ?\017)) ; Shift In - ignored
			   ((eq char ?\^G)
			    (beep t)) ; Bell
			   ((eq char ?\032)
			    (let ((end (string-match "\n" str i)))
			      (if end
				  (progn (funcall term-command-hook
						  (substring str (1+ i) (1- end)))
					 (setq i end))
				(setq term-terminal-parameter
				      (substring str i))
				(setq term-terminal-state 4)
				(setq i str-length))))
			   (t ; insert char FIXME: Should never happen
			    (term-move-columns 1)
			    (backward-delete-char 1)
			    (insert char))))
		    ((eq term-terminal-state 2) ; Seen Esc
		     (cond ((eq char ?\133) ;; ?\133 = ?[
			    (make-local-variable 'term-terminal-parameter)
			    (make-local-variable 'term-terminal-previous-parameter)
			    (setq term-terminal-parameter 0)
			    (setq term-terminal-previous-parameter 0)
			    (setq term-terminal-state 3))
			   ((eq char ?D) ;; scroll forward
			    (term-handle-deferred-scroll)
			    (term-down 1 t)
			    (setq term-terminal-state 0))
			   ((eq char ?M) ;; scroll reversed
			    (term-insert-lines 1)
			    (setq term-terminal-state 0))
			   ((eq char ?7) ;; Save cursor
			    (term-handle-deferred-scroll)
			    (setq term-saved-cursor
				  (cons (term-current-row)
					(term-horizontal-column)))
			    (setq term-terminal-state 0))
			   ((eq char ?8) ;; Restore cursor
			    (if term-saved-cursor
				(term-goto (car term-saved-cursor)
					   (cdr term-saved-cursor)))
			    (setq term-terminal-state 0))
			   ((setq term-terminal-state 0))))
		    ((eq term-terminal-state 3) ; Seen Esc [
		     (cond ((and (>= char ?0) (<= char ?9))
			    (setq term-terminal-parameter
				  (+ (* 10 term-terminal-parameter) (- char ?0))))
			   ((eq char ?\073 ) ; ?;
			    (setq term-terminal-previous-parameter
				  term-terminal-parameter)
			    (setq term-terminal-parameter 0))
			   ((eq char ??)) ; Ignore ? 
			   (t
			    (term-handle-ansi-escape proc char)
			    (setq term-terminal-state 0)))))
	      (if (term-handling-pager)
		  ;; Finish stuff to get ready to handle PAGER.
		  (progn
		    (if (> (% (current-column) term-width) 0)
			(setq term-terminal-parameter
			      (substring str i))
		      ;; We're at column 0.  Goto end of buffer; to compensate,
		      ;; prepend a ?\r for later.  This looks more consistent.
		      (if (zerop i)
			  (setq term-terminal-parameter
				(concat "\r" (substring str i)))
			(setq term-terminal-parameter (substring str (1- i)))
			(aset term-terminal-parameter 0 ?\r))
		      (goto-char (point-max)))
		    (setq term-terminal-state 4)
		    (make-local-variable 'term-pager-old-filter)
		    (setq term-pager-old-filter (process-filter proc))
		    (set-process-filter proc term-pager-filter)
		    (setq i str-length)))
	      (setq i (1+ i))))

	  (if (>= (term-current-row) term-height)
	      (term-handle-deferred-scroll))

	  (set-marker (process-mark proc) (point))
	  (if save-point
	      (progn (goto-char save-point)
		     (set-marker save-point nil)))

	  ;; Check for a pending filename-and-line number to display.
	  ;; We do this before scrolling, because we might create a new window.
	  (if (and term-pending-frame
		   (eq (window-buffer selected) (current-buffer)))
	      (progn (term-display-line (car term-pending-frame)
					(cdr term-pending-frame))
		     (setq term-pending-frame nil)
		 ;; We have created a new window, so check the window size.
		     (term-check-size proc)))

	  ;; Scroll each window displaying the buffer but (by default)
	  ;; only if the point matches the process-mark we started with.
	  (setq win selected)
	  (while (progn
		   (setq win (next-window win nil t))
		   (if (eq (window-buffer win) (process-buffer proc))
		       (let ((scroll term-scroll-to-bottom-on-output))
			 (select-window win)
			 (if (or (= (point) save-marker)
				 (eq scroll t) (eq scroll 'all)
				 ;; Maybe user wants point to jump to the end.
				 (and (eq selected win)
				      (or (eq scroll 'this) (not save-point)))
				 (and (eq scroll 'others)
				      (not (eq selected win))))
			     (progn
			       (goto-char term-home-marker)
			       (recenter 0)
			       (goto-char (process-mark proc))
			       (if (not (pos-visible-in-window-p (point) win))
				   (recenter -1))))
			 ;; Optionally scroll so that the text
			 ;; ends at the bottom of the window.
			 (if (and term-scroll-show-maximum-output
				  (>= (point) (process-mark proc)))
			     (save-excursion
			       (goto-char (point-max))
			       (recenter -1)))))
		   (not (eq win selected))))

	  (set-marker save-marker nil))
      ;; unwind-protect cleanup-forms follow:
      (set-buffer previous-buffer)
      (select-window selected))))

(defun term-handle-deferred-scroll ()
  (let ((count (- (term-current-row) term-height)))
    (if (>= count 0)
	(save-excursion
	  (goto-char term-home-marker)
	  (term-vertical-motion (1+ count))
	  (set-marker term-home-marker (point))
	  (setq term-current-row (1- term-height))))))

;;; Handle a character assuming (eq terminal-state 2) -
;;; i.e. we have previously seen Escape followed by ?[.

(defun term-handle-ansi-escape (proc char)
  (cond
   ((eq char ?H) ; cursor motion
    (if (<= term-terminal-parameter 0)
	(setq term-terminal-parameter 1))
    (if (<= term-terminal-previous-parameter 0)
	(setq term-terminal-previous-parameter 1))
    (if (> term-terminal-previous-parameter term-height)
	(setq term-terminal-previous-parameter term-height))
    (if (> term-terminal-parameter term-width)
	(setq term-terminal-parameter term-width))
    (term-goto
     (1- term-terminal-previous-parameter)
     (1- term-terminal-parameter)))
   ;; \E[A - cursor up
   ((eq char ?A)
    (term-handle-deferred-scroll)
    (term-down (- (max 1 term-terminal-parameter)) t))
   ;; \E[B - cursor down
   ((eq char ?B)
    (term-down (max 1 term-terminal-parameter) t))
   ;; \E[C - cursor right
   ((eq char ?C)
    (term-move-columns (max 1 term-terminal-parameter)))
   ;; \E[D - cursor left
   ((eq char ?D)
    (term-move-columns (- (max 1 term-terminal-parameter))))
   ;; \E[J - clear to end of screen
   ((eq char ?J)
    (term-erase-in-display term-terminal-parameter))
   ;; \E[K - clear to end of line
   ((eq char ?K)
    (term-erase-in-line term-terminal-parameter))
   ;; \E[L - insert lines
   ((eq char ?L)
    (term-insert-lines (max 1 term-terminal-parameter)))
   ;; \E[M - delete lines
   ((eq char ?M)
    (term-delete-lines (max 1 term-terminal-parameter)))
   ;; \E[P - delete chars
   ((eq char ?P)
    (term-delete-chars (max 1 term-terminal-parameter)))
   ;; \E[@ - insert spaces
   ((eq char ?@)
    (term-insert-spaces (max 1 term-terminal-parameter)))
   ;; \E[?h - DEC Private Mode Set
   ((eq char ?h)
    (cond ((eq term-terminal-parameter 4)
	   (setq term-insert-mode t))
	  ((eq term-terminal-parameter 47)
	   (term-switch-to-alternate-sub-buffer t))))
   ;; \E[?l - DEC Private Mode Reset
   ((eq char ?l)
    (cond ((eq term-terminal-parameter 4)
	   (setq term-insert-mode nil))
	  ((eq term-terminal-parameter 47)
	   (term-switch-to-alternate-sub-buffer nil))))
   ;; \E[m - Set/reset standard mode
   ((eq char ?m)
    (cond ((eq term-terminal-parameter 7)
	   (setq term-current-face 'highlight))
	  ((eq term-terminal-parameter 4)
	   (setq term-current-face 'term-underline-face))
	  ((eq term-terminal-parameter 1)
	   (setq term-current-face 'bold))
	  (t (setq term-current-face 'default))))
   ;; \E[6n - Report cursor position
   ((eq char ?n)
    (term-handle-deferred-scroll)
    (process-send-string proc
			 (format "\e[%s;%sR"
				 (1+ (term-current-row))
				 (1+ (term-horizontal-column)))))
   ;; \E[r - Set scrolling region
   ((eq char ?r)
    (term-scroll-region
     (1- term-terminal-previous-parameter)
     term-terminal-parameter))
   (t)))

(defun term-scroll-region (top bottom)
  "Set scrolling region.
TOP is the top-most line (inclusive) of the new scrolling region,
while BOTTOM is the line following the new scrolling region (e.g. exclusive).
The top-most line is line 0."
  (setq term-scroll-start
	(if (or (< top 0) (>= top term-height))
	    0
	  top))
  (setq term-scroll-end
	(if (or (<= bottom term-scroll-start) (> bottom term-height))
	    term-height
	  bottom))
  (setq term-scroll-with-delete
	(or (term-using-alternate-sub-buffer)
	    (not (and (= term-scroll-start 0)
		      (= term-scroll-end term-height))))))

(defun term-switch-to-alternate-sub-buffer (set)
  ;; If asked to switch to (from) the alternate sub-buffer, and already (not)
  ;; using it, do nothing.  This test is needed for some programs (including
  ;; emacs) that emit the ti termcap string twice, for unknown reason.
  (term-handle-deferred-scroll)
  (if (eq set (not (term-using-alternate-sub-buffer)))
      (let ((row (term-current-row))
	    (col (term-horizontal-column)))
	(cond (set
	       (goto-char (point-max))
	       (if (not (eq (preceding-char) ?\n))
		   (term-insert-char ?\n 1))
	       (setq term-scroll-with-delete t)
	       (setq term-saved-home-marker (copy-marker term-home-marker))
	       (set-marker term-home-marker (point)))
	      (t
	       (setq term-scroll-with-delete
		     (not (and (= term-scroll-start 0)
			       (= term-scroll-end term-height))))
	       (set-marker term-home-marker term-saved-home-marker)
	       (set-marker term-saved-home-marker nil)
	       (setq term-saved-home-marker nil)
	       (goto-char term-home-marker)))
	(setq term-current-column nil)
	(setq term-current-row 0)
	(term-goto row col))))

;; Default value for the symbol term-command-hook.

(defun term-command-hook (string)
  (cond ((= (aref string 0) ?\032)
	 ;; gdb (when invoked with -fullname) prints:
	 ;; \032\032FULLFILENAME:LINENUMBER:CHARPOS:BEG_OR_MIDDLE:PC\n
	 (let* ((first-colon (string-match ":" string 1))
		(second-colon
		 (string-match ":" string (1+ first-colon)))
		(filename (substring string 1 first-colon))
		(fileline (string-to-int
			   (substring string (1+ first-colon) second-colon))))
	   (setq term-pending-frame (cons filename fileline))))
	((= (aref string 0) ?/)
	 (cd (substring string 1)))
	;; Allowing the inferior to call functions in emacs is
	;; probably too big a security hole.
	;; ((= (aref string 0) ?!)
	;; (eval (car (read-from-string string 1))))
	(t)));; Otherwise ignore it

;; Make sure the file named TRUE-FILE is in a buffer that appears on the screen
;; and that its line LINE is visible.
;; Put the overlay-arrow on the line LINE in that buffer.
;; This is mainly used by gdb.

(defun term-display-line (true-file line)
  (term-display-buffer-line (find-file-noselect true-file) line))

(defun term-display-buffer-line (buffer line)
  (let* ((window (display-buffer buffer t))
	 (pos))
    (save-excursion
      (set-buffer buffer)
      (save-restriction
	(widen)
	(goto-line line)
	(setq pos (point))
	(setq overlay-arrow-string "=>")
	(or overlay-arrow-position
	    (setq overlay-arrow-position (make-marker)))
	(set-marker overlay-arrow-position (point) (current-buffer)))
      (cond ((or (< pos (point-min)) (> pos (point-max)))
	     (widen)
	     (goto-char pos))))
    (set-window-point window overlay-arrow-position)))

;;; The buffer-local marker term-home-marker defines the "home position"
;;; (in terms of cursor motion).  However, we move the term-home-marker
;;; "down" as needed so that is no more that a window-full above (point-max).

(defun term-goto-home ()
  (term-handle-deferred-scroll)
  (goto-char term-home-marker)
  (setq term-current-row 0)
  (setq term-current-column (current-column))
  (setq term-start-line-column term-current-column))

(defun term-goto (row col)
  (term-handle-deferred-scroll)
  (cond ((and term-current-row (>= row term-current-row))
	 ;; I assume this is a worthwhile optimization.
	 (term-vertical-motion 0)
	 (setq term-current-column term-start-line-column)
	 (setq row (- row term-current-row)))
	(t
	 (term-goto-home)))
  (term-down row)
  (term-move-columns col))

; The page is full, so enter "pager" mode, and wait for input.

(defun term-process-pager ()
  (if (not term-pager-break-map)
      (let* ((map (make-keymap))
	     (i 0) tmp)
;	(while (< i 128)
;	  (define-key map (make-string 1 i) 'term-send-raw)
;	  (setq i (1+ i)))
	(define-key map "\e"
	  (lookup-key (current-global-map) "\e"))
	(define-key map "\C-x"
	  (lookup-key (current-global-map) "\C-x"))
	(define-key map "\C-u"
	  (lookup-key (current-global-map) "\C-u"))
	(define-key map " " 'term-pager-page)
	(define-key map "\r" 'term-pager-line)
	(define-key map "?" 'term-pager-help)
	(define-key map "h" 'term-pager-help)
	(define-key map "b" 'term-pager-back-page)
	(define-key map "\177" 'term-pager-back-line)
	(define-key map "q" 'term-pager-discard)
	(define-key map "D" 'term-pager-disable)
	(define-key map "<" 'term-pager-bob)
	(define-key map ">" 'term-pager-eob)

	;; Add menu bar.
	(term-if-emacs19
	 (term-ifnot-xemacs
	  (define-key map [menu-bar terminal] term-terminal-menu)
	  (define-key map [menu-bar signals] term-signals-menu)
	  (setq tmp (make-sparse-keymap "More pages?"))
	  (define-key tmp [help] '("Help" . term-pager-help))
	  (define-key tmp [disable]
	    '("Disable paging" . term-fake-pager-disable))
	  (define-key tmp [discard]
	    '("Discard remaining output" . term-pager-discard))
	  (define-key tmp [eob] '("Goto to end" . term-pager-eob))
	  (define-key tmp [bob] '("Goto to beginning" . term-pager-bob))
	  (define-key tmp [line] '("1 line forwards" . term-pager-line))
	  (define-key tmp [bline] '("1 line backwards" . term-pager-back-line))
	  (define-key tmp [back] '("1 page backwards" . term-pager-back-page))
	  (define-key tmp [page] '("1 page forwards" . term-pager-page))
	  (define-key map [menu-bar page] (cons "More pages?" tmp))
	  ))

	(setq term-pager-break-map map)))
;  (let ((process (get-buffer-process (current-buffer))))
;    (stop-process process))  
  (setq term-pager-old-local-map (current-local-map))
  (use-local-map term-pager-break-map)
  (make-local-variable 'term-old-mode-line-format)
  (setq term-old-mode-line-format mode-line-format)
  (setq mode-line-format
	(list "--  **MORE**  "
	      mode-line-buffer-identification
	      " [Type ? for help] "
	      "%-"))
  (force-mode-line-update))

(defun term-pager-line (lines)
  (interactive "p")
  (let* ((moved (vertical-motion (1+ lines)))
	 (deficit (- lines moved)))
    (if (> moved lines)
	(backward-char))
    (cond ((<= deficit 0) ;; OK, had enough in the buffer for request.
	   (recenter (1- term-height)))
	  ((term-pager-continue deficit)))))

(defun term-pager-page (arg)
  "Proceed past the **MORE** break, allowing the next page of output to appear"
  (interactive "p")
  (term-pager-line (* arg term-height)))

; Pager mode command to go to beginning of buffer
(defun term-pager-bob ()
  (interactive)
  (goto-char (point-min))
  (if (= (vertical-motion term-height) term-height)
      (backward-char))
  (recenter (1- term-height)))

; pager mode command to go to end of buffer
(defun term-pager-eob ()
  (interactive)
  (goto-char term-home-marker)
  (recenter 0)
  (goto-char (process-mark (get-buffer-process (current-buffer)))))

(defun term-pager-back-line (lines)
  (interactive "p")
  (vertical-motion (- 1 lines))
  (if (not (bobp))
      (backward-char)
    (beep)
    ;; Move cursor to end of window.
    (vertical-motion term-height)
    (backward-char))
  (recenter (1- term-height)))

(defun term-pager-back-page (arg)
  (interactive "p")
  (term-pager-back-line (* arg term-height)))

(defun term-pager-discard ()
  (interactive)
  (setq term-terminal-parameter "")
  (interrupt-process nil t)
  (term-pager-continue term-height))

; Disable pager processing.
; Only callable while in pager mode.  (Contrast term-disable-pager.)
(defun term-pager-disable ()
  (interactive)
  (if (term-handling-pager)
      (term-pager-continue nil)
    (setq term-pager-count nil))
  (term-update-mode-line))
    
; Enable pager processing.
(defun term-pager-enable ()
  (interactive)
  (or (term-pager-enabled)
      (setq term-pager-count 0)) ;; Or maybe set to (term-current-row) ??
  (term-update-mode-line))

(defun term-pager-toggle ()
  (interactive)
  (if (term-pager-enabled) (term-pager-disable) (term-pager-enable)))

(term-ifnot-xemacs
 (defalias 'term-fake-pager-enable 'term-pager-toggle)
 (defalias 'term-fake-pager-disable 'term-pager-toggle)
 (put 'term-char-mode 'menu-enable '(term-in-line-mode))
 (put 'term-line-mode 'menu-enable '(term-in-char-mode))
 (put 'term-fake-pager-enable 'menu-enable '(not term-pager-count))
 (put 'term-fake-pager-disable 'menu-enable 'term-pager-count))

(defun term-pager-help ()
  "Provide help on commands available in a terminal-emulator **MORE** break"
  (interactive)
  (message "Terminal-emulator pager break help...")
  (sit-for 0)
  (with-electric-help
    (function (lambda ()
		(princ (substitute-command-keys
"\\<term-pager-break-map>\
Terminal-emulator MORE break.\n\
Type one of the following keys:\n\n\
\\[term-pager-page]\t\tMove forward one page.\n\
\\[term-pager-line]\t\tMove forward one line.\n\
\\[universal-argument] N \\[term-pager-page]\tMove N pages forward.\n\
\\[universal-argument] N \\[term-pager-line]\tMove N lines forward.\n\
\\[universal-argument] N \\[term-pager-back-line]\tMove N lines back.\n\
\\[universal-argument] N \\[term-pager-back-page]\t\tMove N pages back.\n\
\\[term-pager-bob]\t\tMove to the beginning of the buffer.\n\
\\[term-pager-eob]\t\tMove to the end of the buffer.\n\
\\[term-pager-discard]\t\tKill pending output and kill process.\n\
\\[term-pager-disable]\t\tDisable PAGER handling.\n\n\
\\{term-pager-break-map}\n\
Any other key is passed through to the program
running under the terminal emulator and disables pager processing until
all pending output has been dealt with."))
		nil))))

(defun term-pager-continue (new-count)
  (let ((process (get-buffer-process (current-buffer))))
    (use-local-map term-pager-old-local-map)
    (setq term-pager-old-local-map nil)
    (setq mode-line-format term-old-mode-line-format)
    (force-mode-line-update)
    (setq term-pager-count new-count)
    (set-process-filter process term-pager-old-filter)
    (funcall term-pager-old-filter process "")
    (continue-process process)))

;; Make sure there are DOWN blank lines below the current one.
;; Return 0 if we're unable (because of PAGER handling), else return DOWN.

(defun term-handle-scroll (down)
  (let ((scroll-needed
	 (- (+ (term-current-row) down 1) term-scroll-end)))
    (if (> scroll-needed 0)
	(let ((save-point (copy-marker (point))) (save-top))
	  (goto-char term-home-marker)
	  (cond (term-scroll-with-delete
		 ;; delete scroll-needed lines at term-scroll-start
		 (term-vertical-motion term-scroll-start)
		 (setq save-top (point))
		 (term-vertical-motion scroll-needed)
		 (delete-region save-top (point))
		 (goto-char save-point)
		 (term-vertical-motion down)
		 (term-adjust-current-row-cache (- scroll-needed))
		 (setq term-current-column nil)
		 (term-insert-char ?\n scroll-needed))
		((and (numberp term-pager-count)
		      (< (setq term-pager-count (- term-pager-count down))
			 0))
		 (setq down 0)
		 (term-process-pager))
		(t
		 (term-adjust-current-row-cache (- scroll-needed))
		 (term-vertical-motion scroll-needed)
		 (set-marker term-home-marker (point))))
	  (goto-char save-point)
	  (set-marker save-point nil))))
  down)

(defun term-down (down &optional check-for-scroll)
  "Move down DOWN screen lines vertically."
  (let ((start-column (term-horizontal-column)))
    (if (and check-for-scroll (or term-scroll-with-delete term-pager-count))
	(setq down (term-handle-scroll down)))
    (term-adjust-current-row-cache down)
    (if (/= (point) (point-max))
	(setq down (- down (term-vertical-motion down))))
    ;; Extend buffer with extra blank lines if needed.
    (cond ((> down 0)
	   (term-insert-char ?\n down)
	   (setq term-current-column 0)
	   (setq term-start-line-column 0))
	  (t
	   (setq term-current-column nil)
	   (setq term-start-line-column (current-column))))
    (if start-column
	(term-move-columns start-column))))

;; Assuming point is at the beginning of a screen line,
;; if the line above point wraps around, add a ?\n to undo the wrapping.
;; FIXME:  Probably should be called more than it is.
(defun term-unwrap-line ()
  (if (not (bolp)) (insert-before-markers ?\n)))

(defun term-erase-in-line (kind)
  (if (> kind 1) ;; erase left of point
      (let ((cols (term-horizontal-column)) (saved-point (point)))
	(term-vertical-motion 0)
	(delete-region (point) saved-point)
	(term-insert-char ?\n cols)))
  (if (not (eq kind 1)) ;; erase right of point
      (let ((saved-point (point))
	    (wrapped (and (zerop (term-horizontal-column))
			  (not (zerop (term-current-column))))))
	(term-vertical-motion 1)
	(delete-region saved-point (point))
	;; wrapped is true if we're at the beginning of screen line,
	;; but not a buffer line.  If we delete the current screen line
	;; that will make the previous line no longer wrap, and (because
	;; of the way emacs display works) point will be at the end of
	;; the previous screen line rather then the beginning of the
	;; current one. To avoid that, we make sure that current line
	;; contain a space, to force the previous line to continue to wrap.
	;; We could do this always, but it seems preferable to not add the
	;; extra space when wrapped is false.
	(if wrapped
	    (insert ? ))
	(insert ?\n)
	(put-text-property saved-point (point) 'face 'default)
	(goto-char saved-point))))

(defun term-erase-in-display (kind)
  "Erases (that is blanks out) part of the window.
If KIND is 0, erase from (point) to (point-max);
if KIND is 1, erase from home to point; else erase from home to point-max.
Should only be called when point is at the start of a screen line."
  (term-handle-deferred-scroll)
  (cond ((eq term-terminal-parameter 0)
	 (delete-region (point) (point-max))
	 (term-unwrap-line))
	((let ((row (term-current-row))
	      (col (term-horizontal-column))
	      (start-region term-home-marker)
	      (end-region (if (eq kind 1) (point) (point-max))))
	   (delete-region start-region end-region)
	   (term-unwrap-line)
	   (if (eq kind 1)
	       (term-insert-char ?\n row))
	   (setq term-current-column nil)
	   (setq term-current-row nil)
	   (term-goto row col)))))

(defun term-delete-chars (count)
  (let ((save-point (point)))
    (term-vertical-motion 1)
    (term-unwrap-line)
    (goto-char save-point)
    (move-to-column (+ (term-current-column) count) t)
    (delete-region save-point (point))))

;;; Insert COUNT spaces after point, but do not change any of
;;; following screen lines.  Hence we may have to delete characters
;;; at teh end of this screen line to make room.

(defun term-insert-spaces (count)
  (let ((save-point (point)) (save-eol))
    (term-vertical-motion 1)
    (if (bolp)
	(backward-char))
    (setq save-eol (point))
    (move-to-column (+ (term-start-line-column) (- term-width count)) t)
    (if (> save-eol (point))
	(delete-region (point) save-eol))
    (goto-char save-point)
    (term-insert-char ?  count)
    (goto-char save-point)))

(defun term-delete-lines (lines)
  (let ((start (point))
	(save-current-column term-current-column)
	(save-start-line-column term-start-line-column)
	(save-current-row (term-current-row)))
    (term-down lines)
    (delete-region start (point))
    (term-down (- term-scroll-end save-current-row lines))
    (term-insert-char ?\n lines)
    (setq term-current-column save-current-column)
    (setq term-start-line-column save-start-line-column)
    (setq term-current-row save-current-row)
    (goto-char start)))

(defun term-insert-lines (lines)
  (let ((start (point))
	(start-deleted)
	(save-current-column term-current-column)
	(save-start-line-column term-start-line-column)
	(save-current-row (term-current-row)))
    (term-down (- term-scroll-end save-current-row lines))
    (setq start-deleted (point))
    (term-down lines)
    (delete-region start-deleted (point))
    (goto-char start)
    (setq term-current-column save-current-column)
    (setq term-start-line-column save-start-line-column)
    (setq term-current-row save-current-row)
    (term-insert-char ?\n lines)
    (goto-char start)))

(defun term-set-output-log (name)
  "Record raw inferior process output in a buffer."
  (interactive (list (if term-log-buffer
			 nil
		       (read-buffer "Record output in buffer: "
				    (format "%s output-log"
					    (buffer-name (current-buffer)))
				    nil))))
  (if (or (null name) (equal name ""))
      (progn (setq term-log-buffer nil)
	     (message "Output logging off."))
    (if (get-buffer name)
	nil
      (save-excursion
	(set-buffer (get-buffer-create name))
	(fundamental-mode)
	(buffer-disable-undo (current-buffer))
	(erase-buffer)))
    (setq term-log-buffer (get-buffer name))
    (message "Recording terminal emulator output into buffer \"%s\""
	     (buffer-name term-log-buffer))))

(defun term-stop-photo ()
  "Discontinue raw inferior process logging."
  (interactive)
  (term-set-output-log nil))

(defun term-show-maximum-output ()
  "Put the end of the buffer at the bottom of the window."
  (interactive)
  (goto-char (point-max))
  (recenter -1))

;;; Do the user's customisation...

(defvar term-load-hook nil
  "This hook is run when term is loaded in.
This is a good place to put keybindings.")
	
(run-hooks 'term-load-hook)


;;; Filename/command/history completion in a buffer
;;; ===========================================================================
;;; Useful completion functions, courtesy of the Ergo group.

;;; Six commands:
;;; term-dynamic-complete		Complete or expand command, filename,
;;;                                     history at point.
;;; term-dynamic-complete-filename	Complete filename at point.
;;; term-dynamic-list-filename-completions List completions in help buffer.
;;; term-replace-by-expanded-filename	Expand and complete filename at point;
;;;					replace with expanded/completed name.
;;; term-dynamic-simple-complete	Complete stub given candidates.

;;; These are not installed in the term-mode keymap. But they are
;;; available for people who want them. Shell-mode installs them:
;;; (define-key shell-mode-map "\t" 'term-dynamic-complete)
;;; (define-key shell-mode-map "\M-?"
;;;             'term-dynamic-list-filename-completions)))
;;;
;;; Commands like this are fine things to put in load hooks if you
;;; want them present in specific modes.

(defvar term-completion-autolist nil
  "*If non-nil, automatically list possibilities on partial completion.
This mirrors the optional behavior of tcsh.")

(defvar term-completion-addsuffix t
  "*If non-nil, add a `/' to completed directories, ` ' to file names.
This mirrors the optional behavior of tcsh.")

(defvar term-completion-recexact nil
  "*If non-nil, use shortest completion if characters cannot be added.
This mirrors the optional behavior of tcsh.

A non-nil value is useful if `term-completion-autolist' is non-nil too.")

(defvar term-completion-fignore nil
  "*List of suffixes to be disregarded during file completion.
This mirrors the optional behavior of bash and tcsh.

Note that this applies to `term-dynamic-complete-filename' only.")

(defvar term-file-name-prefix ""
  "Prefix prepended to absolute file names taken from process input.
This is used by term's and shell's completion functions, and by shell's
directory tracking functions.")


(defun term-directory (directory)
  ;; Return expanded DIRECTORY, with `term-file-name-prefix' if absolute.
  (expand-file-name (if (file-name-absolute-p directory)
			(concat term-file-name-prefix directory)
		      directory)))


(defun term-word (word-chars)
  "Return the word of WORD-CHARS at point, or nil if non is found.
Word constituents are considered to be those in WORD-CHARS, which is like the
inside of a \"[...]\" (see `skip-chars-forward')."
  (save-excursion
    (let ((limit (point))
	  (word (concat "[" word-chars "]"))
	  (non-word (concat "[^" word-chars "]")))
      (if (re-search-backward non-word nil 'move)
	  (forward-char 1))
      ;; Anchor the search forwards.
      (if (or (eolp) (looking-at non-word))
	  nil
	(re-search-forward (concat word "+") limit)
	(buffer-substring (match-beginning 0) (match-end 0))))))


(defun term-match-partial-filename ()
  "Return the filename at point, or nil if non is found.
Environment variables are substituted.  See `term-word'."
  (let ((filename (term-word "~/A-Za-z0-9+@:_.$#,={}-")))
    (and filename (substitute-in-file-name filename))))


(defun term-dynamic-complete ()
  "Dynamically perform completion at point.
Calls the functions in `term-dynamic-complete-functions' to perform
completion until a function returns non-nil, at which point completion is
assumed to have occurred."
  (interactive)
  (let ((functions term-dynamic-complete-functions))
    (while (and functions (null (funcall (car functions))))
      (setq functions (cdr functions)))))


(defun term-dynamic-complete-filename ()
  "Dynamically complete the filename at point.
Completes if after a filename.  See `term-match-partial-filename' and
`term-dynamic-complete-as-filename'.
This function is similar to `term-replace-by-expanded-filename', except that
it won't change parts of the filename already entered in the buffer; it just
adds completion characters to the end of the filename.  A completions listing
may be shown in a help buffer if completion is ambiguous.

Completion is dependent on the value of `term-completion-addsuffix',
`term-completion-recexact' and `term-completion-fignore', and the timing of
completions listing is dependent on the value of `term-completion-autolist'.

Returns t if successful."
  (interactive)
  (if (term-match-partial-filename)
      (prog2 (or (eq (selected-window) (minibuffer-window))
		 (message "Completing file name..."))
	  (term-dynamic-complete-as-filename))))

(defun term-dynamic-complete-as-filename ()
  "Dynamically complete at point as a filename.
See `term-dynamic-complete-filename'.  Returns t if successful."
  (let* ((completion-ignore-case nil)
	 (completion-ignored-extensions term-completion-fignore)
	 (success t)
	 (filename (or (term-match-partial-filename) ""))
	 (pathdir (file-name-directory filename))
	 (pathnondir (file-name-nondirectory filename))
	 (directory (if pathdir (term-directory pathdir) default-directory))
	 (completion (file-name-completion pathnondir directory))
	 (mini-flag (eq (selected-window) (minibuffer-window))))
    (cond ((null completion)
           (message "No completions of %s" filename)
	   (setq success nil))
          ((eq completion t)            ; Means already completed "file".
           (if term-completion-addsuffix (insert " "))
           (or mini-flag (message "Sole completion")))
          ((string-equal completion "") ; Means completion on "directory/".
           (term-dynamic-list-filename-completions))
          (t                            ; Completion string returned.
           (let ((file (concat (file-name-as-directory directory) completion)))
             (insert (substring (directory-file-name completion)
                                (length pathnondir)))
             (cond ((symbolp (file-name-completion completion directory))
                    ;; We inserted a unique completion.
                    (if term-completion-addsuffix
                        (insert (if (file-directory-p file) "/" " ")))
                    (or mini-flag (message "Completed")))
                   ((and term-completion-recexact term-completion-addsuffix
                         (string-equal pathnondir completion)
                         (file-exists-p file))
                    ;; It's not unique, but user wants shortest match.
                    (insert (if (file-directory-p file) "/" " "))
                    (or mini-flag (message "Completed shortest")))
                   ((or term-completion-autolist
                        (string-equal pathnondir completion))
                    ;; It's not unique, list possible completions.
                    (term-dynamic-list-filename-completions))
                   (t
                    (or mini-flag (message "Partially completed")))))))
    success))


(defun term-replace-by-expanded-filename ()
  "Dynamically expand and complete the filename at point.
Replace the filename with an expanded, canonicalised and completed replacement.
\"Expanded\" means environment variables (e.g., $HOME) and `~'s are replaced
with the corresponding directories.  \"Canonicalised\" means `..'  and `.' are
removed, and the filename is made absolute instead of relative.  For expansion
see `expand-file-name' and `substitute-in-file-name'.  For completion see
`term-dynamic-complete-filename'."
  (interactive)
  (replace-match (expand-file-name (term-match-partial-filename)) t t)
  (term-dynamic-complete-filename))


(defun term-dynamic-simple-complete (stub candidates)
  "Dynamically complete STUB from CANDIDATES list.
This function inserts completion characters at point by completing STUB from
the strings in CANDIDATES.  A completions listing may be shown in a help buffer
if completion is ambiguous.

Returns nil if no completion was inserted.
Returns `sole' if completed with the only completion match.
Returns `shortest' if completed with the shortest of the completion matches.
Returns `partial' if completed as far as possible with the completion matches.
Returns `listed' if a completion listing was shown.

See also `term-dynamic-complete-filename'."
  (let* ((completion-ignore-case nil)
	 (candidates (mapcar (function (lambda (x) (list x))) candidates))
	 (completions (all-completions stub candidates)))
    (cond ((null completions)
 	   (message "No completions of %s" stub)
	   nil)
 	  ((= 1 (length completions))	; Gotcha!
 	   (let ((completion (car completions)))
 	     (if (string-equal completion stub)
 		 (message "Sole completion")
 	       (insert (substring completion (length stub)))
 	       (message "Completed"))
	     (if term-completion-addsuffix (insert " "))
	     'sole))
 	  (t				; There's no unique completion.
 	   (let ((completion (try-completion stub candidates)))
 	     ;; Insert the longest substring.
 	     (insert (substring completion (length stub)))
 	     (cond ((and term-completion-recexact term-completion-addsuffix
 			 (string-equal stub completion)
 			 (member completion completions))
 		    ;; It's not unique, but user wants shortest match.
 		    (insert " ")
 		    (message "Completed shortest")
		    'shortest)
 		   ((or term-completion-autolist
 			(string-equal stub completion))
 		    ;; It's not unique, list possible completions.
 		    (term-dynamic-list-completions completions)
		    'listed)
 		   (t
		    (message "Partially completed")
		    'partial)))))))


(defun term-dynamic-list-filename-completions ()
  "List in help buffer possible completions of the filename at point."
  (interactive)
  (let* ((completion-ignore-case nil)
	 (filename (or (term-match-partial-filename) ""))
	 (pathdir (file-name-directory filename))
	 (pathnondir (file-name-nondirectory filename))
	 (directory (if pathdir (term-directory pathdir) default-directory))
	 (completions (file-name-all-completions pathnondir directory)))
    (if completions
	(term-dynamic-list-completions completions)
      (message "No completions of %s" filename))))


(defun term-dynamic-list-completions (completions)
  "List in help buffer sorted COMPLETIONS.
Typing SPC flushes the help buffer."
  (let ((conf (current-window-configuration)))
    (with-output-to-temp-buffer "*Completions*"
      (display-completion-list (sort completions 'string-lessp)))
    (message "Hit space to flush")
    (let (key first)
      (if (save-excursion
	    (set-buffer (get-buffer "*Completions*"))
	    (setq key (read-key-sequence nil)
		  first (aref key 0))
	    (and (consp first)
		 (eq (window-buffer (posn-window (event-start first)))
		     (get-buffer "*Completions*"))
		 (eq (key-binding key) 'mouse-choose-completion)))
	  ;; If the user does mouse-choose-completion with the mouse,
	  ;; execute the command, then delete the completion window.
	  (progn
	    (mouse-choose-completion first)
	    (set-window-configuration conf))
	(if (eq first ?\ )
	    (set-window-configuration conf)
	  (setq unread-command-events (listify-key-sequence key)))))))

;;; Converting process modes to use term mode
;;; ===========================================================================
;;; Renaming variables
;;; Most of the work is renaming variables and functions. These are the common
;;; ones:
;;; Local variables:
;;;	last-input-start	term-last-input-start
;;; 	last-input-end		term-last-input-end
;;;	shell-prompt-pattern	term-prompt-regexp
;;;     shell-set-directory-error-hook <no equivalent>
;;; Miscellaneous:
;;;	shell-set-directory	<unnecessary>
;;; 	shell-mode-map		term-mode-map
;;; Commands:
;;;	shell-send-input	term-send-input
;;;	shell-send-eof		term-delchar-or-maybe-eof
;;; 	kill-shell-input	term-kill-input
;;;	interrupt-shell-subjob	term-interrupt-subjob
;;;	stop-shell-subjob	term-stop-subjob
;;;	quit-shell-subjob	term-quit-subjob
;;;	kill-shell-subjob	term-kill-subjob
;;;	kill-output-from-shell	term-kill-output
;;;	show-output-from-shell	term-show-output
;;;	copy-last-shell-input	Use term-previous-input/term-next-input
;;;
;;; SHELL-SET-DIRECTORY is gone, its functionality taken over by
;;; SHELL-DIRECTORY-TRACKER, the shell mode's term-input-filter-functions.
;;; Term mode does not provide functionality equivalent to
;;; shell-set-directory-error-hook; it is gone.
;;;
;;; term-last-input-start is provided for modes which want to munge
;;; the buffer after input is sent, perhaps because the inferior
;;; insists on echoing the input.  The LAST-INPUT-START variable in
;;; the old shell package was used to implement a history mechanism,
;;; but you should think twice before using term-last-input-start
;;; for this; the input history ring often does the job better.
;;; 
;;; If you are implementing some process-in-a-buffer mode, called foo-mode, do
;;; *not* create the term-mode local variables in your foo-mode function.
;;; This is not modular.  Instead, call term-mode, and let *it* create the
;;; necessary term-specific local variables. Then create the
;;; foo-mode-specific local variables in foo-mode.  Set the buffer's keymap to
;;; be foo-mode-map, and its mode to be foo-mode.  Set the term-mode hooks
;;; (term-{prompt-regexp, input-filter, input-filter-functions,
;;; get-old-input) that need to be different from the defaults.  Call
;;; foo-mode-hook, and you're done. Don't run the term-mode hook yourself;
;;; term-mode will take care of it. The following example, from shell.el,
;;; is typical:
;;; 
;;; (defvar shell-mode-map '())
;;; (cond ((not shell-mode-map)
;;;        (setq shell-mode-map (copy-keymap term-mode-map))
;;;        (define-key shell-mode-map "\C-c\C-f" 'shell-forward-command)
;;;        (define-key shell-mode-map "\C-c\C-b" 'shell-backward-command)
;;;        (define-key shell-mode-map "\t" 'term-dynamic-complete)
;;;        (define-key shell-mode-map "\M-?"
;;;          'term-dynamic-list-filename-completions)))
;;;
;;; (defun shell-mode ()
;;;   (interactive)
;;;   (term-mode)
;;;   (setq term-prompt-regexp shell-prompt-pattern)
;;;   (setq major-mode 'shell-mode)
;;;   (setq mode-name "Shell")
;;;   (use-local-map shell-mode-map)
;;;   (make-local-variable 'shell-directory-stack)
;;;   (setq shell-directory-stack nil)
;;;   (add-hook 'term-input-filter-functions 'shell-directory-tracker)
;;;   (run-hooks 'shell-mode-hook))
;;;
;;;
;;; Note that make-term is different from make-shell in that it
;;; doesn't have a default program argument. If you give make-shell
;;; a program name of NIL, it cleverly chooses one of explicit-shell-name,
;;; $ESHELL, $SHELL, or /bin/sh. If you give make-term a program argument
;;; of NIL, it barfs. Adjust your code accordingly...
;;;
;;; Completion for term-mode users
;;; 
;;; For modes that use term-mode, term-dynamic-complete-functions is the
;;; hook to add completion functions to.  Functions on this list should return
;;; non-nil if completion occurs (i.e., further completion should not occur).
;;; You could use term-dynamic-simple-complete to do the bulk of the
;;; completion job.

(provide 'term)

;;; term.el ends here
