lisp/man.el

   1 ;; Read in and display parts of Unix manual.
   2 ;; Copyright (C) 1985, 1986 Free Software Foundation, Inc.
   3
   4 ;; This file is part of GNU Emacs.
   5
   6 ;; GNU Emacs is free software; you can redistribute it and/or modify
   7 ;; it under the terms of the GNU General Public License as published by
   8 ;; the Free Software Foundation; either version 1, or (at your option)
   9 ;; any later version.
  10
  11 ;; GNU Emacs is distributed in the hope that it will be useful,
  12 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 ;; GNU General Public License for more details.
  15
  16 ;; You should have received a copy of the GNU General Public License
  17 ;; along with GNU Emacs; see the file COPYING.  If not, write to
  18 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20 (defun manual-entry (topic &optional section)
  21   "Display the Unix manual entry for TOPIC.
  22 TOPIC is either the title of the entry, or has the form TITLE(SECTION)
  23 where SECTION is the desired section of the manual, as in `tty(4)'."
  24   (interactive "sManual entry (topic): ")
  25   (if (= (length topic) 0)
  26       (error "Must specify topic"))
  27   (if (and (null section)
  28            (string-match "\\`[ \t]*\\([^( \t]+\\)[ \t]*(\\(.+\\))[ \t]*\\'" topic))
  29       (setq section (substring topic (match-beginning 2)
  30                                      (match-end 2))
  31             topic (substring topic (match-beginning 1)
  32                                    (match-end 1))))
  33   (with-output-to-temp-buffer (concat "*" topic " Manual Entry*")
  34     (buffer-disable-undo standard-output)
  35     (save-excursion
  36       (set-buffer standard-output)
  37       (message "Looking for formatted entry for %s%s..."
  38                topic (if section (concat "(" section ")") ""))
  39       (let ((dirlist manual-formatted-dirlist)
  40             (case-fold-search nil)
  41             name)
  42         (if (and section (or (file-exists-p
  43                                (setq name (concat manual-formatted-dir-prefix
  44                                                   (substring section 0 1)
  45                                                   "/"
  46                                                   topic "." section)))
  47                              (file-exists-p
  48                                (setq name (concat manual-formatted-dir-prefix
  49                                                   section
  50                                                   "/"
  51                                                   topic "." section)))))
  52             (insert-man-file name)
  53           (while dirlist
  54             (let* ((dir (car dirlist))
  55                    (name1 (concat dir "/" topic "."
  56                                   (or section
  57                                       (substring
  58                                         dir
  59                                         (1+ (or (string-match "\\.[^./]*$" dir)
  60                                                 -2))))))
  61                    completions)
  62               (if (file-exists-p name1)
  63                   (insert-man-file name1)
  64                 (condition-case ()
  65                     (progn
  66                       (setq completions (file-name-all-completions
  67                                          (concat topic "." (or section ""))
  68                                          dir))
  69                       (while completions
  70                         (insert-man-file (concat dir "/" (car completions)))
  71                         (setq completions (cdr completions))))
  72                   (file-error nil)))
  73               (goto-char (point-max)))
  74             (setq dirlist (cdr dirlist)))))
  75
  76       (if (= (buffer-size) 0)
  77           (progn
  78             (message "No formatted entry, invoking man %s%s..."
  79                      (if section (concat section " ") "") topic)
  80             (if section
  81                 (call-process manual-program nil t nil section topic)
  82                 (call-process manual-program nil t nil topic))
  83             (if (< (buffer-size) 80)
  84                 (progn
  85                   (goto-char (point-min))
  86                   (end-of-line)
  87                   (error (buffer-substring 1 (point)))))))
  88
  89       (message "Cleaning manual entry for %s..." topic)
  90       (nuke-nroff-bs)
  91       (set-buffer-modified-p nil)
  92       (setq buffer-read-only t)
  93       (view-mode nil 'bury-buffer)
  94       (message ""))))
  95
  96 ;; Hint: BS stands form more things than "back space"
  97 (defun nuke-nroff-bs ()
  98   (interactive "*")
  99   ;; Nuke headers: "MORE(1) UNIX Programmer's Manual MORE(1)"
 100   ;; We expext to find a footer just before the header except at the beginning.
 101   (goto-char (point-min))
 102   (while (re-search-forward "^ *\\([A-Za-z][-_.A-Za-z0-9]*([0-9A-Z]+)\\).*\\1$" nil t)
 103     (let (start end)
 104       ;; Put START and END around footer and header and garbage blank lines.
 105       ;; Fixed line counts are risky, but allow us to preserve
 106       ;; significant blank lines.
 107       (setq start (save-excursion (forward-line -10) (point)))
 108       (setq end (save-excursion (forward-line 4) (point)))
 109       (delete-region start end)))
 110   ;; Catch the final footer.
 111   (goto-char (point-max))
 112   (delete-region (point) (save-excursion (forward-line -7) (point)))
 113
 114   ;; Nuke underlining and overstriking (only by the same letter)
 115   (goto-char (point-min))
 116   (while (search-forward "\b" nil t)
 117     (let* ((preceding (char-after (- (point) 2)))
 118            (following (following-char)))
 119       (cond ((= preceding following)
 120              ;; x\bx
 121              (delete-char -2))
 122             ((and (= preceding ?o) (= following ?\+))
 123              ;; o\b+
 124              (delete-char -2))
 125             ((= preceding ?\_)
 126              ;; _\b
 127              (delete-char -2))
 128             ((= following ?\_)
 129              ;; \b_
 130              (delete-region (1- (point)) (1+ (point)))))))
 131
 132   ;; Zap ESC7, ESC8, and ESC9.
 133   ;; This is for Sun man pages like "man 1 csh"
 134   (goto-char (point-min))
 135   (while (re-search-forward "\e[789]" nil t)
 136     (replace-match ""))
 137
 138   ;; Crunch blank lines
 139   (goto-char (point-min))
 140   (while (re-search-forward "\n\n\n\n*" nil t)
 141     (replace-match "\n\n"))
 142
 143   ;; Nuke blanks lines at start.
 144   (goto-char (point-min))
 145   (skip-chars-forward "\n")
 146   (delete-region (point-min) (point)))
 147
 148
 149 (defun insert-man-file (name)
 150   ;; Insert manual file (unpacked as necessary) into buffer
 151   (if (or (equal (substring name -2) ".Z")
 152           (string-match "/cat[0-9][a-z]?\\.Z/" name))
 153       (call-process "zcat" name t nil)
 154     (if (equal (substring name -2) ".z")
 155         (call-process "pcat" nil t nil name)
 156       (insert-file-contents name))))