(decode_coding_charset): Check type of an element of

[bpt/emacs.git] / lisp / man.el

;;; man.el --- browse UNIX manual pages -*- coding: iso-8859-1 -*-

;; Copyright (C) 1993, 1994, 1996, 1997, 2001, 2002, 2003,
;;   2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.

;; Author: Barry A. Warsaw <bwarsaw@cen.com>
;; Maintainer: FSF
;; Keywords: help
;; Adapted-By: ESR, pot

;; This file is part of GNU Emacs.

;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;; This code provides a function, `man', with which you can browse
;; UNIX manual pages.  Formatting is done in background so that you
;; can continue to use your Emacs while processing is going on.
;;
;; The mode also supports hypertext-like following of manual page SEE
;; ALSO references, and other features.  See below or do `?' in a
;; manual page buffer for details.

;; ========== Credits and History ==========
;; In mid 1991, several people posted some interesting improvements to
;; man.el from the standard Emacs 18.57 distribution.  I liked many of
;; these, but wanted everything in one single package, so I decided
;; to incorporate them into a single manual browsing mode.  While
;; much of the code here has been rewritten, and some features added,
;; these folks deserve lots of credit for providing the initial
;; excellent packages on which this one is based.

;; Nick Duffek <duffek@chaos.cs.brandeis.edu>, posted a very nice
;; improvement which retrieved and cleaned the manpages in a
;; background process, and which correctly deciphered such options as
;; man -k.

;; Eric Rose <erose@jessica.stanford.edu>, submitted manual.el which
;; provided a very nice manual browsing mode.

;; This package was available as `superman.el' from the LCD package
;; for some time before it was accepted into Emacs 19.  The entry
;; point and some other names have been changed to make it a drop-in
;; replacement for the old man.el package.

;; Francesco Potorti` <pot@cnuce.cnr.it> cleaned it up thoroughly,
;; making it faster, more robust and more tolerant of different
;; systems' man idiosyncrasies.

;; ========== Features ==========
;; + Runs "man" in the background and pipes the results through a
;;   series of sed and awk scripts so that all retrieving and cleaning
;;   is done in the background.  The cleaning commands are configurable.
;; + Syntax is the same as Un*x man
;; + Functionality is the same as Un*x man, including "man -k" and
;;   "man <section>", etc.
;; + Provides a manual browsing mode with keybindings for traversing
;;   the sections of a manpage, following references in the SEE ALSO
;;   section, and more.
;; + Multiple manpages created with the same man command are put into
;;   a narrowed buffer circular list.

;; ============= TODO ===========
;; - Add a command for printing.
;; - The awk script deletes multiple blank lines.  This behavior does
;;   not allow to understand if there was indeed a blank line at the
;;   end or beginning of a page (after the header, or before the
;;   footer).  A different algorithm should be used.  It is easy to
;;   compute how many blank lines there are before and after the page
;;   headers, and after the page footer.  But it is possible to compute
;;   the number of blank lines before the page footer by heuristics
;;   only.  Is it worth doing?
;; - Allow a user option to mean that all the manpages should go in
;;   the same buffer, where they can be browsed with M-n and M-p.
;; - Allow completion on the manpage name when calling man.  This
;;   requires a reliable list of places where manpages can be found.  The
;;   drawback would be that if the list is not complete, the user might
;;   be led to believe that the manpages in the missing directories do
;;   not exist.

\f
;;; Code:

(eval-when-compile (require 'cl))
(require 'assoc)
(require 'button)

;; vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
;; empty defvars (keep the compiler quiet)

(defgroup man nil
  "Browse UNIX manual pages."
  :prefix "Man-"
  :group 'help)


(defvar Man-notify)
(defcustom Man-filter-list nil
  "*Manpage cleaning filter command phrases.
This variable contains a list of the following form:

'((command-string phrase-string*)*)

Each phrase-string is concatenated onto the command-string to form a
command filter.  The (standard) output (and standard error) of the Un*x
man command is piped through each command filter in the order the
commands appear in the association list.  The final output is placed in
the manpage buffer."
  :type '(repeat (list (string :tag "Command String")
		       (repeat :inline t
			       (string :tag "Phrase String"))))
  :group 'man)

(defvar Man-uses-untabify-flag t
  "Non-nil means use `untabify' instead of `Man-untabify-command'.")
(defvar Man-sed-script nil
  "Script for sed to nuke backspaces and ANSI codes from manpages.")

;; vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
;; user variables

(defcustom Man-fontify-manpage-flag t
  "Non-nil means make up the manpage with fonts."
  :type 'boolean
  :group 'man)

(defcustom Man-overstrike-face 'bold
  "Face to use when fontifying overstrike."
  :type 'face
  :group 'man)

(defcustom Man-underline-face 'underline
  "Face to use when fontifying underlining."
  :type 'face
  :group 'man)

(defcustom Man-reverse-face 'highlight
  "Face to use when fontifying reverse video."
  :type 'face
  :group 'man)

;; Use the value of the obsolete user option Man-notify, if set.
(defcustom Man-notify-method (if (boundp 'Man-notify) Man-notify 'friendly)
  "Selects the behavior when manpage is ready.
This variable may have one of the following values, where (sf) means
that the frames are switched, so the manpage is displayed in the frame
where the man command was called from:

newframe   -- put the manpage in its own frame (see `Man-frame-parameters')
pushy      -- make the manpage the current buffer in the current window
bully      -- make the manpage the current buffer and only window (sf)
aggressive -- make the manpage the current buffer in the other window (sf)
friendly   -- display manpage in the other window but don't make current (sf)
polite     -- don't display manpage, but prints message and beep when ready
quiet      -- like `polite', but don't beep
meek       -- make no indication that the manpage is ready

Any other value of `Man-notify-method' is equivalent to `meek'."
  :type '(radio (const newframe) (const pushy) (const bully)
		(const aggressive) (const friendly)
		(const polite) (const quiet) (const meek))
  :group 'man)

(defcustom Man-width nil
  "Number of columns for which manual pages should be formatted.
If nil, the width of the window selected at the moment of man
invocation is used.  If non-nil, the width of the frame selected
at the moment of man invocation is used.  The value also can be a
positive integer."
  :type '(choice (const :tag "Window width" nil)
                 (const :tag "Frame width" t)
                 (integer :tag "Specific width" :value 65))
  :group 'man)

(defcustom Man-frame-parameters nil
  "Frame parameter list for creating a new frame for a manual page."
  :type 'sexp
  :group 'man)

(defcustom Man-downcase-section-letters-flag t
  "Non-nil means letters in sections are converted to lower case.
Some Un*x man commands can't handle uppercase letters in sections, for
example \"man 2V chmod\", but they are often displayed in the manpage
with the upper case letter.  When this variable is t, the section
letter (e.g., \"2V\") is converted to lowercase (e.g., \"2v\") before
being sent to the man background process."
  :type 'boolean
  :group 'man)

(defcustom Man-circular-pages-flag t
  "Non-nil means the manpage list is treated as circular for traversal."
  :type 'boolean
  :group 'man)

(defcustom Man-section-translations-alist
  (list
   '("3C++" . "3")
   ;; Some systems have a real 3x man section, so let's comment this.
   ;; '("3X" . "3")                        ; Xlib man pages
   '("3X11" . "3")
   '("1-UCB" . ""))
  "Association list of bogus sections to real section numbers.
Some manpages (e.g. the Sun C++ 2.1 manpages) have section numbers in
their references which Un*x `man' does not recognize.  This
association list is used to translate those sections, when found, to
the associated section number."
  :type '(repeat (cons (string :tag "Bogus Section")
		       (string :tag "Real Section")))
  :group 'man)

(defcustom Man-header-file-path
  '("/usr/include" "/usr/local/include")
  "C Header file search path used in Man."
  :type '(repeat string)
  :group 'man)

(defvar manual-program "man"
  "The name of the program that produces man pages.")

(defvar Man-untabify-command "pr"
  "Command used for untabifying.")

(defvar Man-untabify-command-args (list "-t" "-e")
  "List of arguments to be passed to `Man-untabify-command' (which see).")

(defvar Man-sed-command "sed"
  "Command used for processing sed scripts.")

(defvar Man-awk-command "awk"
  "Command used for processing awk scripts.")

(defvar Man-mode-hook nil
  "Hook run when Man mode is enabled.")

(defvar Man-cooked-hook nil
  "Hook run after removing backspaces but before `Man-mode' processing.")