Fix another shr infloop in the filling code

[gnu-emacs] / doc / misc / woman.texi

\input texinfo   @c -*-texinfo-*-
@c %**start of header
@setfilename ../../info/woman
@settitle WoMan: Browse Unix Manual Pages ``W.O. (without) Man''
@include emacsver.texi
@afourpaper
@c With different size paper the printed page breaks will need attention!
@c Look for @page and @need commands.
@setchapternewpage off
@paragraphindent 0
@c %**end of header

@copying
This file documents WoMan: A program to browse Unix manual pages `W.O.
(without) man'.

Copyright @copyright{} 2001--2013 Free Software Foundation, Inc.

@quotation
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with the Front-Cover texts being ``A GNU Manual,''
and with the Back-Cover Texts as in (a) below.  A copy of the license
is included in the section entitled ``GNU Free Documentation License.''

(a) The FSF's Back-Cover Text is: ``You have the freedom to copy and
modify this GNU manual.''
@end quotation
@end copying

@dircategory Emacs misc features
@direntry
* WoMan: (woman).               Browse UN*X Manual Pages "W.O. (without) Man".
@end direntry

@finalout

@titlepage
@title WoMan
@subtitle Browse Unix Manual Pages ``W.O. (without) Man''
@subtitle as distributed with Emacs @value{EMACSVER}
@author Francis J. Wright
@sp 2
@author School of Mathematical Sciences
@author Queen Mary and Westfield College
@author (University of London)
@author Mile End Road, London E1 4NS, UK
@author @email{F.J.Wright@@qmul.ac.uk}
@author @uref{http://centaur.maths.qmw.ac.uk/}
@c He no longer maintains this manual.

@comment  The following two commands start the copyright page.
@page
@vskip 0pt plus 1filll
@insertcopying
@end titlepage

@contents

@c ===================================================================

@ifnottex
@node Top
@top WoMan: Browse Unix Manual Pages ``W.O. (without) Man''

@display
As distributed with Emacs @value{EMACSVER}.

@ifnothtml
@email{F.J.Wright@@qmw.ac.uk, Francis J. Wright}
@end ifnothtml
@ifhtml
Francis J. Wright
@end ifhtml
@uref{http://centaur.maths.qmw.ac.uk/, School of Mathematical Sciences}
Queen Mary and Westfield College (University of London)
Mile End Road, London E1 4NS, UK
@end display

@insertcopying
@end ifnottex

@menu
* Introduction::        Introduction
* Background::          Background
* Finding::             Finding and Formatting Man Pages
* Browsing::            Browsing Man Pages
* Customization::       Customization
* Log::                 The *WoMan-Log* Buffer
* Technical::           Technical Details
* Bugs::                Reporting Bugs
* Acknowledgments::     Acknowledgments
* GNU Free Documentation License:: The license for this documentation.
* Command Index::       Command Index
* Variable Index::      Variable Index
* Keystroke Index::     Keystroke Index
* Concept Index::       Concept Index
@end menu

@c ===================================================================

@node Introduction
@chapter Introduction
@cindex introduction

This version of WoMan should run with GNU Emacs 20.3 or later on any
platform.  It has not been tested, and may not run, with any other
version of Emacs.  It was developed primarily on various versions of
Microsoft Windows, but has also been tested on MS-DOS, and various
versions of UNIX and GNU/Linux.

WoMan is distributed with GNU Emacs.

WoMan implements a subset of the formatting performed by the Emacs
@code{man} (or @code{manual-entry}) command to format a Unix-style
@dfn{manual page} (usually abbreviated to @dfn{man page}) for display,
but without calling any external programs.  It is intended to emulate
the whole of the @code{roff -man} macro package, plus those @code{roff}
requests (@pxref{Background, , Background}) that are most commonly used
in man pages.  However, the emulation is modified to include the
reformatting done by the Emacs @code{man} command.  No hyphenation is
performed.

@table @b
@item Advantages
Much more direct, does not require any external programs.  Supports
completion on man page names.
@item Disadvantages
Not a complete emulation.  Currently no support for @code{eqn} or
@code{tbl}.  Slightly slower for large man pages (but usually faster for
small- and medium-size pages).
@end table

This browser works quite well on simple well-written man files.  It
works less well on idiosyncratic files that ``break the rules'' or use
the more obscure @code{roff} requests directly.  Current test results
are available in the file
@uref{http://centaur.maths.qmw.ac.uk/Emacs/WoMan/files/woman.status,
@file{woman.status}}.

WoMan supports the use of compressed man files via
@code{auto-compression-mode} by turning it on if necessary.  But you may
need to adjust the user option @code{woman-file-compression-regexp}.
@xref{Interface Options, , Interface Options}.

Brief help on the WoMan interactive commands and user options, all of
which begin with the prefix @code{woman-} (or occasionally
@code{WoMan-}), is available most easily by loading WoMan and then
either running the command @code{woman-mini-help} or selecting the WoMan
menu option @samp{Mini Help}.

Guidance on reporting bugs is given below.  @xref{Bugs, , Reporting Bugs}.

@c ===================================================================

@node Background
@chapter Background
@cindex background

WoMan is a browser for traditional Unix-style manual page documentation.
Each such document is conventionally referred to as a @dfn{manual page},
or @dfn{man page} for short, even though some are very much longer than
one page.  A man page is a document written using the Unix ``man''
macros, which are themselves written in the nroff/troff text processing
markup language.  @code{nroff} and @code{troff} are text processors
originally written for the UNIX operating system by Joseph F. Ossanna at
Bell Laboratories, Murray Hill, New Jersey, USA@.  They are closely
related, and except in the few cases where the distinction between them
is important I will refer to them both ambiguously as @code{roff}.

@code{roff} markup consists of @dfn{requests} and @dfn{escape
sequences}.  A request occupies a complete line and begins with either a
period or a single forward quote.  An escape sequences is embedded
within the input text and begins (by default) with a backslash.  The
original man macro package defines 20 new @code{roff} requests
implemented as macros, which were considered to be sufficient for
writing man pages.  But whilst in principle man pages use only the man
macros, in practice a significant number use many other @code{roff}
requests.

The distinction between @code{troff} and @code{nroff} is that
@code{troff} was designed to drive a phototypesetter whereas
@code{nroff} was designed to produce essentially @acronym{ASCII} output for a
character-based device similar to a teletypewriter (usually abbreviated
to ``teletype'' or ``tty'').  Hence, @code{troff} supports much finer
control over output positioning than does @code{nroff} and can be seen
as a forerunner of @TeX{}.  Traditionally, man pages are either
formatted by @code{troff} for typesetting or by @code{nroff} for
printing on a character printer or displaying on a screen.  Of course,
over the last 25 years or so, the distinction between typeset output on
paper and characters on a screen has become blurred by the fact that
most screens now support bit-mapped displays, so that any information
that can be printed can also be rendered on screen, the only difference
being the resolution.

Nevertheless, Unix-style manual page documentation is still normally
browsed on screen by running a program called @code{man}.  This program
looks in a predefined set of directories for the man page matching a
specified topic, then either formats the source file by running
@code{nroff} or recovers a pre-formatted file, and displays it via a
pager such as @code{more}.  @code{nroff} normally formats for a printer,
so it paginates the output, numbers the pages, etc., most of which is
irrelevant when the document is browsed as a continuous scrollable
document on screen.  The only concession to on-screen browsing normally
implemented by the @code{man} program is to squeeze consecutive blank
lines into a single blank line.

For some time, Emacs has offered an improved interface for browsing man
pages in the form of the Emacs @code{man} (or @code{manual-entry})
command, see @ref{Documentation, man, Documentation Commands, emacs, GNU
Emacs Manual}.
This command runs @code{man} as described above, perhaps in
the background, and then post-processes the output to remove much of the
@code{nroff} pagination such as page headers and footers, and places the
result into an Emacs buffer.  It puts this buffer into a special major
mode, which is tailored for man page browsing, and provides a number of
useful navigation commands, support for following references, etc.  It
provides some support for special display faces (fonts), but no special
menu or mouse support.  The Emacs man package appears to have been
developed over about 10 years, from the late 1980s to the late 1990s.

There is considerable inefficiency in having @code{nroff} paginate a
document and then removing most of the pagination!

WoMan is an Emacs Lisp library that provides an emulation of the
functionality of the Emacs @code{man} command, the main difference being
that WoMan does not use any external programs.  The only situation in
which WoMan might use an external program is when the source file is
compressed, when WoMan will use the standard Emacs automatic
decompression facility, which does call an external program.

I began developing WoMan in the Spring of 1997 and the first version was
released in May 1997.  The original motivation for WoMan was the fact
that many GNU and Unix programs are ported to other platforms and come
with Unix-style manual page documentation.  This may be difficult to
read because ports of the Unix-style @code{man} program can be a little
awkward to set up.  I decided that it should not be too hard to emulate
the 20 @code{man} macros directly, without treating them as macros and
largely ignoring the underlying @code{roff} requests, given the text
processing capabilities of Emacs.  This proved to be essentially true,
and it did not take a great deal of work to be able to format simple man
pages acceptably.

One problem arose with the significant number of man pages that use
@code{roff} requests in addition to the @code{man} macros, and since
releasing the first version of WoMan I have been continually extending
it to support more @code{roff} requests.  WoMan can now format a
significant proportion of the man pages that I have tested, either well
or at least readably.  However, I have added capabilities partly by
making additional passes through the document, a design that is
fundamentally flawed.  This can only be solved by a major re-design of
WoMan to handle the major formatting within a single recursive pass,
rather than the present multiple passes without any significant
recursion.  There are some @code{roff} requests that cannot be handled
satisfactorily within the present design.  Some of these are currently
handled by kludges that ``usually more or less work.''

The principle advantage of WoMan is that it does not require @code{man},
and indeed the name WoMan is a contraction of ``without man.''  But it
has other advantages.  It does not paginate the document, so it does not
need to un-paginate it again, thereby saving time.  It could take full
advantage of the display capabilities available to it, and I hope to
develop WoMan to take advantage of developments in Emacs itself.  At
present, WoMan uses several display faces to support bold and italic
text, to indicate other fonts, etc.  The default faces are also
colored, but the choice of faces is customizable.  WoMan provides menu
support for navigation and mouse support for following references, in
addition to the navigation facilities provided by @code{man} mode.
WoMan has (this) texinfo documentation!

WoMan @emph{does not} replace @code{man}, although it does use a number
of the facilities implemented in the Emacs @code{man} library.  WoMan
and man can happily co-exist, which is very useful for comparison and
debugging purposes.

@ignore
@code{nroff} simulates non-@acronym{ASCII} characters by using one or more
@acronym{ASCII} characters.  WoMan should be able to do much better than
this.  I have recently begun to add support for WoMan to use more of the
characters in its default font and to use a symbol font, and it is an
aspect that I intend to develop further in the near future.  It should
be possible to move WoMan from an emulation of @code{nroff} to an
emulation of @code{troff} as GNU Emacs moves to providing bit-mapped
display facilities.
@end ignore

@node Finding
@chapter Finding and Formatting Man Pages
@cindex using, finding man pages
@cindex using, formatting man pages
@cindex finding man pages
@cindex formatting man pages
@cindex man pages, finding
@cindex man pages, formatting

WoMan provides three user interfaces for finding and formatting man pages:

@itemize @bullet
@item
a topic interface similar to that provided by the standard Emacs
@code{man} command;

@item
a family of filename interfaces analogous to the standard Emacs
@code{view-file} command;

@item
an automatic interface that detects the file type from its contents.
(This is currently neither well tested, well supported nor recommended!)
@end itemize

The topic and filename interfaces support completion in the usual way.

The topic interface is generally the most convenient for regular use,
although it may require some special setup, especially if your machine
does not already have a conventional @code{man} installation (which
WoMan tries to detect).

The simplest filename interface command @code{woman-find-file} can
always be used with no setup at all (provided WoMan is installed and
loaded or set up to autoload).

The automatic interface always requires special setup.


@heading Case-Dependence of Filenames

@cindex case-sensitivity
@vindex w32-downcase-file-names
By default, WoMan ignores case in file pathnames only when it seems
appropriate.  Microsoft Windows users who want complete case
independence should set the special NTEmacs variable
@code{w32-downcase-file-names} to @code{t} and use all lower case when
setting WoMan file paths.


@menu
* Topic::               Topic Interface
* Filename::            Filename Interface
* Automatic::           Automatic Interface
@end menu

@node Topic
@section Topic Interface
@cindex topic interface

The topic interface is accessed principally via the command
@code{woman}.  The same command can be accessed via the menu item
@samp{Help->Manuals->Read Man Page (WoMan)...} once WoMan has been
loaded.  The command reads a manual topic in the minibuffer, which can
be the @dfn{basename} of a man file anywhere in the man file
structure.  The ``basename'' in this context means the filename
without any directory component and without any extension or suffix
components that relate to the file type.  So, for example, if there is
a compressed source file in Chapter 5 of the UNIX Programmer's Manual
with the full pathname @file{/usr/local/man/man5/man.conf.5.gz} then
the topic is @code{man.conf}.  Provided WoMan is configured correctly,
this topic will appear among the completions offered by @code{woman}.
If more than one file has the same topic name then WoMan will prompt
for which file to format.  Completion of topics is case insensitive.

Clearly, @code{woman} has to know where to look for man files and there
are two customizable user options that store this information:
@code{woman-manpath} and @code{woman-path}.  @xref{Interface Options, ,
Interface Options}.  If @code{woman-manpath} is not set explicitly then
WoMan tries to pick up the information that would be used by the
@code{man} command, as follows.  If the environment variable
@code{MANPATH} is set, which seems to be the standard mechanism under
UNIX, then WoMan parses that.  Otherwise, if WoMan can find a
configuration file named (by default) @file{man.conf} (or something very
similar), which seems to be the standard mechanism under GNU/Linux, then
it parses that.  To be precise, ``something very similar'' means
starting with @samp{man} and ending with @samp{.conf} and possibly more
lowercase letters, e.g., @file{manual.configuration}.
The search path and/or precise full path name for this file are set by
the value of the customizable user option @code{woman-man.conf-path}.
If all else fails, WoMan uses a plausible default man search path.

If the above default configuration does not work correctly for any
reason then simply customize the value of @code{woman-manpath}.  To
access man files that are not in a conventional man file hierarchy,
customize the value of @code{woman-path} to include the directories
containing the files.  In this way, @code{woman} can access manual files
@emph{anywhere} in the entire file system.

There are two differences between @code{woman-manpath} and
@code{woman-path}.  Firstly, the elements of @code{woman-manpath} must
be directories that contain @emph{directories of} man files, whereas the
elements of @code{woman-path} must be directories that contain man files
@emph{directly}.  Secondly, the last directory component of each element
of @code{woman-path} is treated as a regular (Emacs) match expression
rather than a fixed name, which allows collections of related
directories to be specified succinctly.  Also, elements of
@code{woman-manpath} can be conses, indicating a mapping from
@samp{PATH} environment variable components to man directory
hierarchies.

For topic completion to work, WoMan must build a list of all the manual
files that it can access, which can be very slow, especially if a
network is involved.  For this reason, it caches various amounts of
information, after which retrieving it from the cache is very fast.  If
the cache ever gets out of synchronism with reality, running the
@code{woman} command with a prefix argument (e.g., @kbd{C-u M-x woman})
will force it to rebuild its cache.  This is necessary only if the names
or locations of any man files change; it is not necessary if only their
contents change.  It would always be necessary if such a change occurred
whilst Emacs were running and after WoMan has been loaded.  It may be
necessary if such a change occurs between Emacs sessions and persistent
caching is used, although WoMan can detect some changes that invalidate
its cache and rebuild it automatically.

Customize the variable @code{woman-cache-filename} to save the cache
between Emacs sessions.  This is recommended only if the @code{woman}
command is too slow the first time it is run in an Emacs session, while
it builds its cache in main memory, which @emph{may} be @emph{very}
slow.  @xref{Cache, , The WoMan Topic Cache}, for further details.


@menu
* Cache::               The WoMan Topic Cache
* Word at point::       Using the "Word at Point" as a Topic Suggestion
@end menu

@node Cache
@subsection The WoMan Topic Cache
@cindex topic cache
@cindex cache, topic

The amount of information that WoMan caches (in main memory and,
optionally, saved to disc) is controlled by the user option
@code{woman-cache-level}.  There is a trade-off between the speed with
which WoMan can find a file and the size of the cache, and the default
setting gives a reasonable compromise.

The @code{woman} command always performs a certain amount of caching in
main memory, but it can also write its cache to the filestore as a
persistent cache under control of the user option
@code{woman-cache-filename}.  If persistent caching is turned on then
WoMan re-loads its internal cache from the cache file almost
instantaneously, so that there is never any perceptible start-up delay
@emph{except} when WoMan rebuilds its cache.  Persistent caching is
currently turned off by default.  This is because users with persistent
caching turned on may overlook the need to force WoMan to rebuild its
cache the first time they run it after they have installed new man
files; with persistent caching turned off, WoMan automatically rebuilds
its cache every time it is run in a new Emacs session.

A prefix argument always causes the @code{woman} command (only) to
rebuild its topic cache, and to re-save it to
@code{woman-cache-filename} if this variable has a non-@code{nil} value.  This
is necessary if the @emph{names} of any of the directories or files in
the paths specified by @code{woman-manpath} or @code{woman-path} change.
If WoMan user options that affect the cache are changed then WoMan will
automatically update its cache file on disc (if one is in use) the next
time it is run in a new Emacs session.


@node Word at point
@subsection Using the "Word at Point" as a Topic Suggestion
@cindex word at point
@cindex point, word at

By default, the @code{woman} command uses the word nearest to point in
the current buffer as a suggestion for the topic to look up, if it
exists as a valid topic.  The topic can be confirmed or edited in the
minibuffer.

You can also bind the variable @code{woman-use-topic-at-point} locally
to a non-@code{nil} value (using @code{let}), in which case
@code{woman} will can use the suggested topic without confirmation if
possible.  This may be useful to provide special private key bindings,
e.g., this key binding for @kbd{C-c w} runs WoMan on the topic at
point without seeking confirmation:

@lisp
(global-set-key "\C-cw"
                (lambda ()
                  (interactive)
                  (let ((woman-use-topic-at-point t))
                    (woman))))
@end lisp


@node Filename
@section Filename Interface
@cindex filename interface

The commands in this family are completely independent of the topic
interface, caching mechanism, etc.

@findex woman-find-file
The filename interface is accessed principally via the extended command
@code{woman-find-file}, which is available without any configuration at
all (provided WoMan is installed and loaded or set up to autoload).
This command can be used to browse any accessible man file, regardless
of its filename or location.  If the file is compressed then automatic
file decompression must already be turned on (e.g., see the
@samp{Help->Options} submenu)---it is turned on automatically only by
the @code{woman} topic interface.

@findex woman-dired-find-file
Once WoMan is loaded (or if specially set up), various additional
commands in this family are available.  In a dired buffer, the command
@code{woman-dired-find-file} allows the file on the same line as point
to be formatted and browsed by WoMan.  It is bound to the key @kbd{W} in
the dired mode map and added to the dired major mode menu.  It may also
be bound to @kbd{w}, unless this key is bound by another library, which
it is by @code{dired-x}, for example.  Because it is quite likely that
other libraries will extend the capabilities of such a commonly used
mode as dired, the precise key bindings added by WoMan to the dired mode
map are controlled by the user option @code{woman-dired-keys}.

@findex woman-tar-extract-file
When a tar (Tape ARchive) file is visited in Emacs, it is opened in tar
mode, which parses the tar file and shows a dired-like view of its
contents.  The WoMan command @code{woman-tar-extract-file} allows the
file on the same line as point to be formatted and browsed by WoMan.  It
is bound to the key @kbd{w} in the tar mode map and added to the tar
major mode menu.

The command @code{woman-reformat-last-file}, which is bound to the key
@kbd{R} in WoMan mode and available on the major mode menu, reformats
the last file formatted by WoMan.  This may occasionally be useful if
formatting parameters, such as the fill column, are changed, or perhaps
if the buffer is somehow corrupted.

@findex woman-decode-buffer
The command @code{woman-decode-buffer} can be used to decode and browse
the current buffer if it is visiting a man file, although it is
primarily used internally by WoMan.


@node Automatic
@section Automatic Interface
@cindex automatic interface

Emacs provides an interface to detect automatically the format of a file
and decode it when it is visited.  It is used primarily by the
facilities for editing rich (i.e., formatted) text, as a way to store
formatting information transparently as @acronym{ASCII} markup.  WoMan can in
principle use this interface, but it must be configured explicitly.

This use of WoMan does not seem to be particularly advantageous, so it
is not really supported.  It originated during early experiments on how
best to implement WoMan, before I implemented the current topic
interface, and I subsequently stopped using it.  I might revive it as a
mechanism for storing pre-formatted WoMan files, somewhat analogous to
the standard Unix @code{catman} facility.  In the meantime, it exists
for anyone who wants to experiment with it.  Once it is set up it is
simply a question of visiting the file and there is no WoMan-specific
user interface!

To use it, put something like this in your @file{.emacs} file.  [The
call to @code{set-visited-file-name} is to avoid font-locking triggered
by automatic major mode selection.]

@lisp
(autoload 'woman-decode-region "woman")

(add-to-list 'format-alist
             '(man "Unix man-page source format" "\\.\\(TH\\|ig\\) "
                   woman-decode-region nil nil
                   (lambda (arg)
                     set-visited-file-name
                     (file-name-sans-extension buffer-file-name))))
@end lisp

@c ===================================================================

@node Browsing
@chapter Browsing Man Pages
@cindex using, browsing man pages
@cindex browsing man pages
@cindex man pages, browsing

Once a man page has been found and formatted, WoMan provides a browsing
interface that is essentially the same as that provided by the standard
Emacs @code{man} command (and much of the code is inherited from the
@code{man} library, which WoMan currently requires).  Many WoMan
facilities can be accessed from the WoMan major mode menu as well as via
key bindings, etc.

WoMan does not produce any page breaks or page numbers, and in fact does
not paginate the man page at all, since this is not appropriate for
continuous online browsing.  It produces a document header line that is
constructed from the standard man page header and footer.  Apart from
that, the appearance of the formatted man page should be almost
identical to what would be produced by @code{man}, with consecutive
blank lines squeezed to a single blank line.

@menu
* Fonts::               Fonts and Faces
* Navigation::          Navigation
* References::          Following References
* Changing::            Changing the Current Man Page
* Convenience::         Convenience Key Bindings
* Imenu::               Imenu Support; Contents Menu
@end menu

@node Fonts
@section Fonts and Faces
@cindex fonts
@cindex faces

Fonts used by @code{roff} are handled by WoMan as faces, the details of
which are customizable.  @xref{Faces, , Faces}.  WoMan supports both the
italic and bold fonts normally used in man pages, together with a single
face to represent all unknown fonts (which are occasionally used in
``non-standard'' man pages, usually to represent a ``typewriter'' font)
and a face to indicate additional symbols introduced by WoMan.  This
currently means the characters ^ and _ used to indicate super- and
sub-scripts, which are not displayed well by WoMan.


@node Navigation
@section Navigation
@cindex navigation

Man (and hence WoMan) mode can be thought of as a superset of view mode.
The buffer cannot be edited, so keys that would normally self-insert are
used for navigation.  The WoMan key bindings are a minor modification of
the @code{man} key bindings.

@table @kbd
@item @key{SPC}
@kindex SPC
@findex scroll-up
Scroll the man page up the window (@code{scroll-up}).

@item @key{DEL}
@itemx @key{S-SPC}
@kindex DEL
@kindex S-SPC
@findex scroll-down
Scroll the man page down the window (@code{scroll-down}).

@item n
@kindex n
@findex Man-next-section
Move point to the Nth next section---default 1 (@code{Man-next-section}).

@item p
@kindex p
@findex Man-previous-section
Move point to Nth previous section---default 1
(@code{Man-previous-section}).

@item g
@kindex g
@findex Man-goto-section
Move point to the specified section (@code{Man-goto-section}).

@item s
@kindex s
@findex Man-goto-see-also-section
Move point to the ``SEE ALSO'' section
(@code{Man-goto-see-also-section}).  Actually the section moved to is
described by @code{Man-see-also-regexp}.
@end table


@node References
@section Following References
@cindex following references
@cindex references

Man pages usually contain a ``SEE ALSO'' section containing references
to other man pages.  If these man pages are installed then WoMan can
easily be directed to follow the reference, i.e., to find and format the
man page.  When the mouse is passed over a correctly formatted reference
it is highlighted, in which case clicking the middle button
@kbd{Mouse-2} will cause WoMan to follow the reference.  Alternatively,
when point is over such a reference the key @key{RET} will follow the
reference.

Any word in the buffer can be used as a reference by clicking
@kbd{Mouse-2} over it provided the Meta key is also used (although in
general such a ``reference'' will not lead to a man page).
Alternatively, the key @kbd{r} allows completion to be used to select a
reference to follow, based on the word at point as default.

@table @kbd
@item @kbd{Mouse-2}
@kindex Mouse-2
@findex woman-mouse-2
Run WoMan with word under mouse as topic (@code{woman-mouse-2}).  The
word must be mouse-highlighted unless @code{woman-mouse-2} is used with
the Meta key.

@item @key{RET}
@kindex RET
@findex man-follow
Get the man page for the topic under (or nearest to) point
(@code{man-follow}).

@item r
@kindex r
@findex Man-follow-manual-reference
Get one of the man pages referred to in the ``SEE ALSO'' section
(@code{Man-follow-manual-reference}).  Specify which reference to use;
default is based on word at point.
@end table


@node Changing
@section Changing the Current Man Page
@cindex changing current man page
@cindex current man page, changing

The man page currently being browsed by WoMan can be changed in several
ways.  The command @code{woman} can be invoked to format another man
page, or the current WoMan buffer can be buried or killed.  WoMan
maintains a ring of formatted man pages, and it is possible to move
forwards and backwards in this ring by moving to the next or previous
man page.  It is sometimes useful to reformat the current page, for
example after the right margin (the wrap column) or some other
formatting parameter has been changed.

Buffers formatted by Man and WoMan are completely unrelated, even though
some of the commands to manipulate them are superficially the same (and
share code).

@table @kbd
@item m
@kindex m
@findex man
Run the command @code{man} to get a Un*x manual page and put it in a
buffer.  This command is the top-level command in the man package.  It
runs a Un*x command to retrieve and clean a man page in the background
and places the results in a Man mode (man page browsing) buffer.  If a
man buffer already exists for this man page, it will display
immediately.  This works exactly the same if WoMan is loaded, except
that the formatting time is displayed in the mini-buffer.

@item w
@kindex w
@findex woman
Run the command @code{woman} exactly as if the extended command or menu
item had been used.

@item q
@kindex q
@findex Man-quit
Bury the buffer containing the current man page (@code{Man-quit}),
i.e., move it to the bottom of the buffer stack.

@item k
@kindex k
@findex Man-kill
Kill the buffer containing the current man page (@code{Man-kill}),
i.e., delete it completely so that it can be retrieved only by formatting
the page again.

@item M-p
@kindex M-p
@findex WoMan-previous-manpage
Find the previous WoMan buffer (@code{WoMan-previous-manpage}).

@item M-n
@kindex M-n
@findex WoMan-next-manpage
Find the next WoMan buffer (@code{WoMan-next-manpage}).

@item R
@kindex R
@findex woman-reformat-last-file
Call WoMan to reformat the last man page formatted by WoMan
(@code{woman-reformat-last-file}), e.g., after changing the fill column.
@end table


@node Convenience
@section Convenience Key Bindings
@cindex convenience key bindings
@cindex key bindings, convenience

@table @kbd
@item -
@kindex -
@findex negative-argument
Begin a negative numeric argument for the next command
(@code{negative-argument}).

@item 0 .. 9
@kindex 0 .. 9
@findex digit-argument
Part of the numeric argument for the next command
(@code{digit-argument}).

@item <
@kindex <
@itemx .
@kindex .
@findex beginning-of-buffer
Move point to the beginning of the buffer; leave mark at previous
position (@code{beginning-of-buffer}).

@item >
@kindex >
@findex end-of-buffer
Move point to the end of the buffer; leave mark at previous position
(@code{end-of-buffer}).

@item ?
@kindex ?
@findex describe-mode
Display documentation of current major mode and minor modes
(@code{describe-mode}).  The major mode description comes first,
followed by the minor modes, each on a separate page.
@end table


@node Imenu
@section Imenu Support; Contents Menu
@cindex imenu support
@cindex contents menu

The WoMan menu provides an option to make a contents menu for the
current man page (using @code{imenu}).  Alternatively, if you customize
the option @code{woman-imenu} to @code{t} then WoMan will do it
automatically for every man page.  The menu title is set by the option
@code{woman-imenu-title}, which is ``CONTENTS'' by default.  The menu
shows manual sections and subsections by default, but you can change
this by customizing @code{woman-imenu-generic-expression}.

WoMan is configured not to replace spaces in an imenu
@code{*Completion*} buffer.  For further documentation on the use of
imenu, such as menu sorting, see the source file @file{imenu.el}, which
is distributed with GNU Emacs.

@c ===================================================================

@node Customization
@chapter Customization
@cindex customization

All WoMan user options are customizable, and it is recommended to
change them only via the standard Emacs customization facilities.
WoMan defines a top-level customization group called @code{WoMan}
under the parent group @code{Help}.  It can be accessed either via the
standard Emacs facilities, e.g., via the @samp{Help->Customize}
submenu, or via the WoMan major mode menu.

The top-level WoMan group contains only a few general options and three
subgroups.  The hooks are provided only for special purposes that, for
example, require code to be executed, and should be changed only via
@code{Customization} or the function @code{add-hook}.  Most
customization should be possible via existing user options.

@vtable @code
@item woman-show-log
A boolean value that defaults to @code{nil}.  If non-@code{nil} then show the
@code{*WoMan-Log*} buffer if appropriate, i.e., if any warning messages
are written to it.  @xref{Log, , The *WoMan-Log* Buffer}.

@item woman-pre-format-hook
A hook run immediately before formatting a buffer.  It might, for
example, be used for face customization.  @xref{Faces, , Faces},
however.

@item woman-post-format-hook
A hook run immediately after formatting a buffer.  It might, for
example, be used for installing a dynamic menu using @code{imenu}.
(However. in this case it is better to use the built-in WoMan
@code{imenu} support.  @xref{Imenu, , Imenu Support; Contents Menu}.)
@end vtable

@heading Customization Subgroups

@table @code
@item WoMan Interface
These options control the process of locating the appropriate file to
browse, and the appearance of the browsing interface.

@item WoMan Formatting
These options control the layout that WoMan uses to format the man page.

@item WoMan Faces
These options control the display faces that WoMan uses to format the
man page.
@end table

@menu
* Interface Options::
* Formatting Options::
* Faces::
* Special symbols::
@end menu

@node Interface Options
@section Interface Options
@cindex interface options

These options control the process of locating the appropriate file to
browse, and the appearance of the browsing interface.

@vtable @code
@item woman-man.conf-path
A list of strings representing directories to search and/or files to try
for a man configuration file.  The default is

@lisp
("/etc" "/usr/local/lib")
@end lisp

@noindent
[for GNU/Linux and Cygwin respectively.]  A trailing separator (@file{/}
for UNIX etc.)@: on directories is optional and the filename matched if a
directory is specified is the first to match the regexp
@code{man.*\.conf}.  If the environment variable @code{MANPATH} is not
set but a configuration file is found then it is parsed instead (or as
well) to provide a default value for @code{woman-manpath}.

@item woman-manpath
A list of strings representing @emph{directory trees} to search for Unix
manual files.  Each element should be the name of a directory that
contains subdirectories of the form @file{man?}, or more precisely
subdirectories selected by the value of @code{woman-manpath-man-regexp}.
Non-directory and unreadable files are ignored.  This can also contain
conses, with the car indicating a @code{PATH} variable component mapped
to the directory tree given in the cdr.

@cindex @code{MANPATH}, environment variable
If not set then the environment variable @code{MANPATH} is used.  If no
such environment variable is found, the default list is determined by
consulting the man configuration file if found.  By default this is
expected to be either @file{/etc/man.config} or
@file{/usr/local/lib/man.conf}, which is controlled by the user option
@code{woman-man.conf-path}.  An empty substring of @code{MANPATH}
denotes the default list.  Otherwise, the default value of this variable
is

@lisp
("/usr/man" "/usr/local/man")
@end lisp

Any environment variables (names of which must have the Unix-style form
@code{$NAME}, e.g., @code{$HOME}, @code{$EMACSDATA}, @code{$EMACS_DIR},
regardless of platform) are evaluated first but each element must
evaluate to a @emph{single} directory name.  Trailing @file{/}s are
ignored.  (Specific directories in @code{woman-path} are also searched.)

On Microsoft platforms I recommend including drive letters explicitly,
e.g.:

@lisp
("C:/Cygwin/usr/man" "C:/usr/man" "C:/usr/local/man")
@end lisp

@cindex directory separator character
@cindex @code{MANPATH}, directory separator
The @code{MANPATH} environment variable may be set using DOS
semi-colon-separated or Unix-style colon-separated syntax (but not
mixed).

@item woman-manpath-man-regexp
A regular expression to match man directories @emph{under} the
@code{woman-manpath} directories.  These normally have names of the form
@file{man?}.  Its default value is @code{"[Mm][Aa][Nn]"}, which is
case-insensitive mainly for the benefit of Microsoft platforms.  Its
purpose is to avoid directories such as @file{cat?}, @file{.},
@file{..}, etc.

@item woman-path
A list of strings representing @emph{specific directories} to search for
Unix manual files.  For example

@lisp
("/emacs/etc")
@end lisp

These directories are searched in addition to the directory trees
specified in @code{woman-manpath}.  Each element should be a directory
string or @code{nil}, which represents the current directory when the
path is expanded and cached.  However, the last component (only) of each
directory string is treated as a regexp (Emacs, not shell) and the
string is expanded into a list of matching directories.  Non-directory
and unreadable files are ignored.  The default value on MS-DOS is

@lisp
("$DJDIR/info" "$DJDIR/man/cat[1-9onlp]")
@end lisp

@noindent
and on other platforms is @code{nil}.

Any environment variables (names of which must have the Unix-style form
@code{$NAME}, e.g., @code{$HOME}, @code{$EMACSDATA}, @code{$EMACS_DIR},
regardless of platform) are evaluated first but each element must
evaluate to a @emph{single} directory name (regexp, see above).  For
example

@lisp
("$EMACSDATA")
@end lisp

@noindent
or equivalently

@lisp
("$EMACS_DIR/etc")
@end lisp

@noindent
Trailing @file{/}s are discarded.  (The directory trees in
@code{woman-manpath} are also searched.)  On Microsoft platforms I
recommend including drive letters explicitly.

@item woman-cache-level
A positive integer representing the level of topic caching:

@enumerate
@item
cache only the topic and directory lists (uses minimal memory, but not
recommended);
@item
cache also the directories for each topic (faster, without using much
more memory);
@item
cache also the actual filenames for each topic (fastest, but uses twice
as much memory).
@end enumerate

The default value is currently 2, a good general compromise.  If the
@code{woman} command is slow to find files then try 3, which may be
particularly beneficial with large remote-mounted man directories.  Run
the @code{woman} command with a prefix argument or delete the cache file
@code{woman-cache-filename} for a change to take effect.  (Values < 1
behave like 1; values > 3 behave like 3.)

@item woman-cache-filename
Either a string representing the full pathname of the WoMan directory
and topic cache file, or @code{nil}.  It is used to save and restore the
cache between Emacs sessions.  This is especially useful with
remote-mounted man page files!  The default value of @code{nil}
suppresses this action.  The ``standard'' non-@code{nil} filename is
@file{~/.wmncach.el}.  Remember that a prefix argument forces the
@code{woman} command to update and re-write the cache.

@item woman-dired-keys
A list of @code{dired} mode keys to be defined to run WoMan on the
current file, e.g., @code{("w" "W")} or any non-@code{nil} atom to
automatically define @kbd{w} and @kbd{W} if they are unbound, or
@code{nil} to do nothing.  Default is @code{t}.

@item woman-imenu-generic-expression
Imenu support for Sections and Subsections: an alist with elements of
the form @code{(MENU-TITLE REGEXP INDEX)}---see the documentation for
@code{imenu-generic-expression}.  Default value is

@lisp
((nil "\n\\([A-Z].*\\)" 1)  ; SECTION, but not TITLE
 ("*Subsections*" "^   \\([A-Z].*\\)" 1))
@end lisp

@item woman-imenu
A boolean value that defaults to @code{nil}.  If non-@code{nil} then WoMan adds
a Contents menu to the menubar by calling @code{imenu-add-to-menubar}.

@item woman-imenu-title
A string representing the title to use if WoMan adds a Contents menu to
the menubar.  Default is @code{"CONTENTS"}.

@item woman-use-topic-at-point
A boolean value that defaults to @code{nil}.  If non-@code{nil} then
the @code{woman} command uses the word at point as the topic,
@emph{without interactive confirmation}, if it exists as a topic.

@item woman-use-topic-at-point-default
A boolean value representing the default value for
@code{woman-use-topic-at-point}.  The default value is @code{nil}.
[The variable @code{woman-use-topic-at-point} may be @code{let}-bound
when @code{woman} is loaded, in which case its global value does not
get defined.  The function @code{woman-file-name} sets it to this
value if it is unbound.]

@item woman-uncompressed-file-regexp
A regular match expression used to select man source files (ignoring any
compression extension).  The default value is
@code{"\\.\\([0-9lmnt]\\w*\\)"} [which means a filename extension is
required].

@emph{Do not change this unless you are sure you know what you are doing!}

The SysV standard man pages use two character suffixes, and this is
becoming more common in the GNU world.  For example, the man pages in
the @code{ncurses} package include @file{toe.1m}, @file{form.3x}, etc.

@strong{Please note:} an optional compression regexp will be appended,
so this regexp @emph{must not} end with any kind of string terminator
such as @code{$} or @code{\\'}.

@item woman-file-compression-regexp
A regular match expression used to match compressed man file extensions
for which decompressors are available and handled by auto-compression
mode.  It should begin with @code{\\.} and end with @code{\\'} and
@emph{must not} be optional.  The default value is
@code{"\\.\\(g?z\\|bz2\\|xz\\)\\'"}, which matches the @code{gzip},
@code{bzip2}, and @code{xz} compression extensions.

@emph{Do not change this unless you are sure you know what you are doing!}

[It should be compatible with the @code{car} of
@code{jka-compr-file-name-handler-entry}, but that is unduly
complicated, includes an inappropriate extension (@file{.tgz}) and is
not loaded by default!]

@item woman-use-own-frame
If non-@code{nil} then use a dedicated frame for displaying WoMan windows.
This is useful only when WoMan is run under a window system such as X or
Microsoft Windows that supports real multiple frames, in which case the
default value is non-@code{nil}.
@end vtable


@node Formatting Options
@section Formatting Options
@cindex formatting options

These options control the layout that WoMan uses to format the man page.

@vtable @code
@item woman-fill-column
An integer specifying the right margin for formatted text.  Default is
65.

@item woman-fill-frame
A boolean value.  If non-@code{nil} then most of the frame width is used,
overriding the value of @code{woman-fill-column}.  Default is @code{nil}.

@item woman-default-indent
An integer specifying the default prevailing indent for the @code{-man}
macros.  Default is 5.  Set this variable to 7 to emulate GNU/Linux man
formatting.

@item woman-bold-headings
A boolean value.  If non-@code{nil} then embolden section and subsection
headings.  Default is @code{t}.  [Heading emboldening is @emph{not} standard
@code{man} behavior.]

@item woman-ignore
A boolean value.  If non-@code{nil} then unrecognized requests etc. are
ignored.  Default is @code{t}.  This gives the standard @code{roff} behavior.
If @code{nil} then they are left in the buffer, which may aid debugging.

@item woman-preserve-ascii
A boolean value.  If non-@code{nil} then preserve @acronym{ASCII} characters in the
WoMan buffer.  Otherwise, non-@acronym{ASCII} characters (that display as
@acronym{ASCII}) may remain, which is irrelevant unless the buffer is to be
saved to a file.  Default is @code{nil}.

@item woman-emulation
WoMan emulation, currently either @code{nroff} or @code{troff}.  Default
is @code{nroff}.  @code{troff} emulation is experimental and largely
untested.
@end vtable


@node Faces
@section Faces
@cindex faces

These options control the display faces that WoMan uses to format the
man page.

@vtable @code
@item woman-fontify
A boolean value.  If non-@code{nil} then WoMan assumes that face support is
available.  It defaults to a non-@code{nil} value if the display supports
either colors or different fonts.

@item woman-italic-face
Face for italic font in man pages.  Default: italic, underlined,
foreground red.  This is overkill!  @code{troff} uses just italic;
@code{nroff} uses just underline.  You should probably select either
italic or underline as you prefer, but not both, although italic and
underline work together perfectly well!

@item woman-bold-face
Face for bold font in man pages.  Default: bold, foreground blue.

@item woman-unknown-face
Face for all unknown fonts in man pages.  Default: foreground brown.
Brown is a good compromise: it is distinguishable from the default but
not enough so as to make font errors look terrible.  (Files that use
non-standard fonts seem to do so badly or in idiosyncratic ways!)

@item woman-addition-face
Face for all additions made by WoMan to man pages.
Default: foreground orange.
@end vtable


@node Special symbols
@section Special symbols
@cindex special symbols

This section currently applies @emph{only} to Microsoft Windows.

WoMan provides partial experimental support for special symbols,
initially only for MS-Windows and only for MS-Windows fonts.  This
includes both non-@acronym{ASCII} characters from the main text font and use
of a separate symbol font.  Later, support will be added for other font
types (e.g., @code{bdf} fonts) and for the X Window System.  In Emacs
20.7, the current support works partially under Windows 9x but may not
work on any other platform.

@vtable @code
@item woman-use-extended-font
A boolean value.  If non-@code{nil} then WoMan may use non-@acronym{ASCII} characters
from the default font.  Default is @code{t}.

@item woman-use-symbol-font
A boolean value.  If non-@code{nil} then WoMan may use the symbol font.
Default is @code{nil}, mainly because it may change the line spacing (at
least in NTEmacs 20).

@item woman-symbol-font
A string describing the symbol font to use for special characters.
It should be compatible with, and the same size as, the default text font.
Under MS-Windows, the default is

@lisp
"-*-Symbol-normal-r-*-*-*-*-96-96-p-*-ms-symbol"
@end lisp
@end vtable


@c ===================================================================

@node Log
@chapter The *WoMan-Log* Buffer
@cindex log buffer
@cindex buffer, log

This is modeled on the Emacs byte-compiler.  It logs all files
formatted by WoMan and the time taken.  If WoMan finds anything that it
cannot handle then it writes a warning to this buffer.  If the variable
@code{woman-show-log} is non-@code{nil} (by default it is @code{nil}) then
WoMan automatically displays this buffer.  @xref{Interface Options, ,
Interface Options}.  Many WoMan warnings can be completely ignored,
because they are reporting the fact that WoMan has ignored requests that
it is correct for WoMan to ignore.  In some future version this level of
paranoia may be reduced, but not until WoMan is deemed more reliable.
At present, all warnings should be treated with some suspicion.
Uninterpreted escape sequences are also logged (in some cases).

By resetting the variable @code{woman-ignore} to @code{nil} (by default
it is @code{t}), uninterpreted @code{roff} requests can optionally be
left in the formatted buffer to indicate precisely where they occurred.
@xref{Interface Options, , Interface Options}.

@c ===================================================================

@node Technical
@chapter Technical Details
@cindex technical details
@cindex horizontal spacing
@cindex spacing, horizontal and vertical
@cindex vertical spacing
@cindex resolution

@heading Horizontal and vertical spacing and resolution

WoMan currently assumes 10 characters per inch horizontally, hence a
horizontal resolution of 24 basic units, and 5 lines per inch
vertically, hence a vertical resolution of 48 basic units.
(@code{nroff} uses 240 per inch.)

@heading Vertical spacing and blank lines

The number of consecutive blank lines in the formatted buffer should be
either 0 or 1.  A blank line should leave a space like .sp 1.
Current policy is to output vertical space only immediately before text
is output.

@c ===================================================================

@node Bugs
@chapter Reporting Bugs
@cindex reporting bugs
@cindex bugs, reporting

If WoMan fails completely, or formats a file incorrectly (i.e.,
obviously wrongly or significantly differently from @code{man}) or
inelegantly, then please

@enumerate
@item
try the latest version of @file{woman.el} from the Emacs repository
on @uref{http://savannah.gnu.org/projects/emacs/}.  If it still fails, please

@item
use @kbd{M-x report-emacs-bug} to send a bug report.
Please include the entry from the
@code{*WoMan-Log*} buffer relating to the problem file, together with
a brief description of the problem.  Please indicate where you got the
man source file from, but do not send it unless asked to send it.
@end enumerate

@c ===================================================================

@node Acknowledgments
@chapter Acknowledgments
@cindex acknowledgments

For Heather, Kathryn and Madelyn, the women in my life (although they
will probably never use it)!

I also thank the following for helpful suggestions, bug reports, code
fragments, general interest, etc.:

@quotation
@c jari.aalto@@cs.tpu.fi
Jari Aalto,
@c dean@@dra.com
Dean Andrews,
@c barranquero@@laley-actualidad.es
Juanma Barranquero,
@c kb@@cs.umb.edu
Karl Berry,
@c jchapman@@netcomuk.co.uk
Jim Chapman,
@c frederic.corne@@erli.fr
Frederic Corne,
@c craft@@alacritech.com
Peter Craft,
@c ccurley@@trib.com
Charles Curley,
@c jdavidso@@teknowledge.com
Jim Davidson,
@c Kevin.DElia@@mci.com
Kevin D'Elia,
@c jpff@@maths.bath.ac.uk
John Fitch,
@c jwfrosch@@rish.b17c.ingr.com
Hans Frosch,
@c ggp@@informix.com
Guy Gascoigne-Piggford,
@c gorkab@@sanchez.com
Brian Gorka,
@c nhe@@lyngso-industri.dk
Nicolai Henriksen,
@c the@@software-ag.de
Thomas Herchenroeder,
@c ahinds@@thegrid.net
Alexander Hinds,
@c sth@@hacon.de
Stefan Hornburg,
@c tjump@@cais.com
Theodore Jump,
@c paulk@@mathworks.com
Paul Kinnucan,
@c jonas@@init.se
Jonas Linde,
@c andrewm@@optimation.co.nz
Andrew McRae,
@c howard@@silverstream.com
Howard Melman,
@c dennis@@math.binghamton.edu
Dennis Pixton,
@c raman@@Adobe.com
T. V. Raman,
@c bruce.ravel@@nist.gov
Bruce Ravel,
@c benny@@crocodial.de
Benjamin Riefenstahl,
@c kruland@@seistl.com
Kevin Ruland,
@c tom@@platte.com
Tom Schutter,
@c wxshi@@ma.neweb.ne.jp
Wei-Xue Shi,
@c fabio@@joplin.colorado.edu
Fabio Somenzi,
@c ks@@ic.uva.nl
Karel Sprenger,
@c szurgot@@itribe.net
Chris Szurgot,
@c pat@@po.cwru.edu
Paul A. Thompson,
@c arrigo@@maths.qmw.ac.uk
Arrigo Triulzi,
@c voelker@@cs.washington.edu
Geoff Voelker,
@c eliz@@is.elta.co.il
Eli Zaretskii
@end quotation

@c ===================================================================

@comment END OF MANUAL TEXT
@page


@node GNU Free Documentation License
@appendix GNU Free Documentation License
@include doclicense.texi

@node Command Index
@unnumbered Command Index

@printindex fn

@node Variable Index
@unnumbered Variable Index

@printindex vr

@c Without a page throw here, the page length seems to get reset to the
@c depth of the index that fits on the page after the previous index.
@c This must be a bug!

@page

@node Keystroke Index
@unnumbered Keystroke Index

@printindex ky

@c Without a page throw here, the page length seems to get reset to the
@c depth of the index that fits on the page after the previous index.
@c This must be a bug!

@page

@node Concept Index
@unnumbered Concept Index

@printindex cp

@bye