Import the htmlfontify manual

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

\input texinfo
@c documentation for htmlfontify
@c written by Vivek Dasmohapatra

@comment %**start of header (This is for running Texinfo on a region.)

@setfilename htmlfontify.info
@settitle Htmlfontify User Manual

@dircategory Emacs
@direntry 
* Htmlfontify: (htmlfontify).    A source code -> linked html + css transformer
@end direntry

@exampleindent 2
@comment %**end of header (This is for running Texinfo on a region.)

@ifinfo

This file documents Htmlfontify, a source code -> crosslinked + formatted +
syntax colourised html transformer.

Copyright (c) 2002,2003 Vivek Dasmohapatra <vivek@@etla.org>

Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation Licence,
Version 1.1 or any later version published by the Free Software
Foundation; with no Invariant Sections, no Front-Cover Texts and
no Back-Cover Texts.  A copy of the licence is included in the
section entitled "GNU Free Documentation Licence".

@end ifinfo

@titlepage
@title Htmlfontify User Manual
@sp 4
@subtitle Htmlfontify version 0.20
@sp 1
@subtitle Jun 2002
@sp 5
@author Vivek Dasmohapatra
@page

@vskip 0pt plus 1filll
@noindent
Copyright @copyright{} 2002 Vivek Dasmohapatra <vivek@@etla.org>

Permission is granted to copy, distribute and/or modify this document 
under the terms of the GNU Free Documentation Licence, Version 1.1 or 
any later version published by the Free Software Foundation; with no 
Invariant Sections, no Front-Cover Texts and no Back-Cover Texts.  A 
copy of the licence is included in the section entitled "GNU Free 
Documentation Licence".

@end titlepage
@page

@node Top, Introduction, (dir), (dir)

@menu
* Introduction::                   About Htmlfontify.
* Usage & Examples::               How to use Htmlfontify.
* Customisation::                  Fine tuning Htmlfontify's behaviour.
* Requirements::                   External programs used by Htmlfontify.
* Index::                          Index of Contents.
* COPYING::                        The GNU Free Documentation Licence.
@end menu

@node Introduction, Usage & Examples, Top, Top
@chapter Introduction
@cindex Introduction

Htmlfontify provides a means of converting individual emacs buffers, 
source files, or entire source trees to html, preserving formatting 
and emacs colourisation / syntax highlighting as much as possible 
through careful application of CSS stylesheets and html tags.

It can also turn instances of functions, methods and ( for some 
languages ) variables and other constructs and items into links 
to their definitions, and create an index file ( or files ) of 
all such symbols, also linked to their points of definition.

Htmlfontify also provides several customisation items, which should 
allow it to mesh more-or-less seamlessly with various templating or 
publishing systems ( in the event, for instance, that you don't want 
to produce the html pages directly ).

@node Usage & Examples, Customisation, Introduction, Top
@chapter Usage & Examples
@cindex Usage & Examples

Htmlfontify can be used both interactively and as part of another 
elisp function. If you're running it in emacs21 ( its native land,
it were ), it will also run when attached to a terminal ( ie w/o X ) 
or even when in batch mode.

@menu
* Interactive::               Using htmlfontify interactively.
* Non-interactive::           Using htmlfontify from elisp.
* Variables::                 Variables (other than customisation entries).
* Data Structures::           Important Data Structures.
* Examples::                  Example(s) of htmlfontify in use.
@end menu

@node Interactive, Non-interactive, , Usage & Examples
@section Interactive
@cindex Interactive
@cindex functions (interactive)

Htmlfontify provides the following interactive functions:

@table @code
@item htmlfontify-buffer
@findex htmlfontify-buffer
@anchor{htmlfontify-buffer}

@lisp

(htmlfontify-buffer &optional @var{srcdir} @var{file})
@end lisp

Create a new buffer, named for the current buffer + a .html extension,
containing an inline css-stylesheet and formatted css-markup html that
reproduces the look of the current emacs buffer as closely as possible.

``Dangerous'' characters in the existing buffer are turned into html 
entities, so you should even be able to do html-within-html fontified 
display. 

You should, however, note that random control or eight-bit characters
such as ^L (\x0c) or ¤ (\xa4) won't get mapped yet.

If the @var{srcdir} and @var{file} arguments are set, lookup etags 
derived entries in the @ref{hfy-tags-cache} and add html anchors 
and hyperlinks as appropriate.

@item htmlfontify-run-etags
@findex htmlfontify-run-etags
@anchor{htmlfontify-run-etags}

@lisp

(htmlfontify-run-etags @var{srcdir})
@end lisp

Load the etags cache for @var{srcdir}. See @ref{hfy-load-tags-cache}.

@item htmlfontify-copy-and-link-dir
@findex htmlfontify-copy-and-link-dir
@anchor{htmlfontify-copy-and-link-dir}

@lisp

(htmlfontify-copy-and-link-dir @var{srcdir} @var{dstdir} &optional @var{f-ext} @var{l-ext})
@end lisp

Trawl @var{srcdir} and write fontified-and-hyperlinked output in 
@var{dstdir} @var{f-ext} and @var{l-ext} specify values for 
@ref{hfy-extn} and @ref{hfy-link-extn}.

You may also want to set @ref{hfy-page-header} and @ref{hfy-page-footer}.

@item htmlfontify-load-rgb-file
@findex htmlfontify-load-rgb-file
@anchor{htmlfontify-load-rgb-file}

@lisp

(htmlfontify-load-rgb-file &optional @var{file})
@end lisp

Load an X11 style rgb.txt file (search @code{hfy-rgb-load-path} if 
@var{file} is not specified).

Note that this is not necessary if all you want is the standard X11
(XFree86 4.1.0) colour name -> rgb triplet mapping, htmlfontify has 
a copy built in, for use when it cannot contact an X server.

Loads the variable @code{hfy-rgb-txt-colour-map}, which is used by
@ref{hfy-fallback-colour-values}.

@item htmlfontify-unload-rgb-file
@findex htmlfontify-unload-rgb-file
@anchor{htmlfontify-unload-rgb-file}

@lisp

(htmlfontify-unload-rgb-file)
@end lisp

Unload the currently loaded X11 style rgb.txt file ( if any ).
@end table

@node Non-interactive, Variables, Interactive, Usage & Examples
@section Non-interactive
@cindex Noninteractive
@cindex functions (noninteractive)

In addition to the aforementioned interactive methods, htmlfontify
provides the following non-interactive ones:

@table @code
@comment  AUTOGENERATED BLOCK

@item hfy-face-to-style
@findex hfy-face-to-style
@anchor{hfy-face-to-style}

@lisp

(hfy-face-to-style @var{fn})
@end lisp

Take @var{fn}, a font or @code{defface} style font specification,
(as returned by @code{face-attr-construct} or @ref{hfy-face-attr-for-class}) 
and return a @ref{hfy-style-assoc}.

See also: @ref{hfy-face-to-style-i}, @ref{hfy-flatten-style}.

@item hfy-fallback-colour-values
@findex hfy-fallback-colour-values
@anchor{hfy-fallback-colour-values}

@lisp

(hfy-fallback-colour-values @var{colour-string})
@end lisp

Use a fallback method for obtaining the rgb values for a colour.
If @ref{htmlfontify-load-rgb-file} has been called, it uses the
colour map specified, otherwise it uses htmlfontify's built in map.

@item hfy-combined-face-spec
@findex hfy-combined-face-spec
@anchor{hfy-combined-face-spec}

@lisp

(hfy-combined-face-spec @var{face})
@end lisp

Return a @code{defface} style alist of possible specifications for 
@var{face}, with any entries resulting from user customisation 
(@code{custom-set-faces}) taking precedence.

See also: @ref{hfy-default-face-def}

@item hfy-word-regex
@findex hfy-word-regex
@anchor{hfy-word-regex}

@lisp

(hfy-word-regex @var{string})
@end lisp

Return a regex that matches @var{string} as the first @code{match-string}, 
with non word characters on either side (vaguely emulating the perl @code{\b} 
regex atom).

@item hfy-force-fontification
@findex hfy-force-fontification
@anchor{hfy-force-fontification}

@lisp

(hfy-force-fontification)
@end lisp

Emacs' fontification is designed for interactive use. As such, it sometimes 
does things like deferring fontification until a section of the buffer is 
exposed and rendered, or until emacs is idle for a while. Sometimes, in 
non-interactive circumstances, or if it can't see X, it doesn't bother 
with some of the harder stuff. While this is all great from the perspective
of a user waiting for emacs to load a 20000 line file and colourise it, 
it's a pain from the point of view from non-interactive code. This function
lies, cheats, steals and generally bullies emacs into fontifying a buffer
from start to finish, with all the extra frills, whether it thinks it nneds
to or not. Oh yes: it operates on the current buffer.

@item hfy-link-style-string
@findex hfy-link-style-string
@anchor{hfy-link-style-string}

@lisp

(hfy-link-style-string @var{style-string})
@end lisp

Replace the end of a css style declaration @var{style-string} with the contents
of the variable @ref{hfy-src-doc-link-style}, removing text matching the 
regex @ref{hfy-src-doc-link-unstyle} first, if necessary.


@item hfy-prepare-index-i
@findex hfy-prepare-index-i
@anchor{hfy-prepare-index-i}

@lisp

(hfy-prepare-index-i @var{srcdir} @var{dstdir} @var{filename} &optional @var{stub} @var{map})
@end lisp

Prepare a tags index buffer for @var{srcdir}.
@ref{hfy-tags-cache} must already have an entry for @var{srcdir} for 
this to work. @ref{hfy-page-header}, @ref{hfy-page-footer}, 
@ref{hfy-link-extn} and @ref{hfy-extn} all play a part here.

If @var{stub} is set, prepare an (appropriately named) index buffer
specifically for entries beginning with @var{stub}.

If @var{map} is set, use that instead of @ref{hfy-tags-cache}.

@item hfy-compile-stylesheet
@findex hfy-compile-stylesheet
@anchor{hfy-compile-stylesheet}

@lisp

(hfy-compile-stylesheet)
@end lisp

Trawl the current buffer, construct and return a @ref{hfy-sheet-assoc}.

@item hfy-css-name
@findex hfy-css-name
@anchor{hfy-css-name}

@lisp

(hfy-css-name @var{fn})
@end lisp

Strip some of the boring bits from a font-name and return a css style 
name. If @var{fn} is a @code{defface} attribute list, either construct
a name for it, store it in the cache, and return it, or just fetch it
from the cache if it's already there.

@item hfy-make-directory
@findex hfy-make-directory
@anchor{hfy-make-directory}

@lisp

(hfy-make-directory @var{dir})
@end lisp

Approx equivalent of mkdir -p @var{dir}

@item hfy-triplet
@findex hfy-triplet
@anchor{hfy-triplet}

@lisp

(hfy-triplet @var{colour})
@end lisp

Takes a colour name (string) and return a CSS rgb(R, G, B) triplet string.
Uses the definition of "white" to map the numbers to the 0-255 range, so
if you've redefined white, (esp if you've redefined it to have a triplet
member lower than that of the colour you are processing, strange things
may happen).

@item hfy-default-footer
@findex hfy-default-footer
@anchor{hfy-default-footer}

@lisp

(hfy-default-footer @var{file})
@end lisp

Default value for @ref{hfy-page-footer}

@item hfy-list-files
@findex hfy-list-files
@anchor{hfy-list-files}

@lisp

(hfy-list-files @var{directory})
@end lisp

Return a list of files under @var{directory}.
Strips any leading "./" from each filename.

@item hfy-colour-vals
@findex hfy-colour-vals
@anchor{hfy-colour-vals}

@lisp

(hfy-colour-vals @var{colour})
@end lisp

Where @var{colour} is a colour name or #XXXXXX style triplet, return a list of 
3 (16 bit) rgb values for said colour. If a window system is unavailable,
calls @ref{hfy-fallback-colour-values}.

@item hfy-href-stub
@findex hfy-href-stub
@anchor{hfy-href-stub}

@lisp

(hfy-href-stub @var{this-file} @var{def-files} @var{tag})
@end lisp

Return an href stub for a tag href: if @var{def-files} (list of files 
containing definitions for the tag in question) contains only one entry,
the href should link straight to that file. Otherwise, the link should 
be to the index file.

We are not yet concerned with the file extensions/tag line number and 
so on at this point.

If @ref{hfy-split-index} is set, and the href wil be to an index file 
rather than a source file, append a .X to @ref{hfy-index-file}, where 
X is the uppercased first character of @var{tag}.

See also: @ref{hfy-relstub}, @ref{hfy-index-file}.

@item hfy-line-number
@findex hfy-line-number
@anchor{hfy-line-number}

@lisp

(hfy-line-number)
@end lisp

Returns the line number of the point in the current buffer.

@item hfy-merge-adjacent-spans
@findex hfy-merge-adjacent-spans
@anchor{hfy-merge-adjacent-spans}

@lisp

(hfy-merge-adjacent-spans @var{face-map})
@end lisp

Where @var{face-map} is a @ref{hfy-facemap-assoc} for the current buffer, 
this function merges adjacent style blocks which are of the same value
and are separated by nothing more interesting than whitespace.

@code{<span class="foo">narf</span> <span class="foo">brain</span>}

(as interpreted from @var{face-map}) would become:

@code{<span class="foo">narf brain</span>}

Returns a modified copy of @var{face-map} (also a @ref{hfy-facemap-assoc}).

@item hfy-mark-tag-names
@findex hfy-mark-tag-names
@anchor{hfy-mark-tag-names}

@lisp

(hfy-mark-tag-names @var{srcdir} @var{file})
@end lisp

Mark tags in @var{file} (lookup @var{srcdir} in @ref{hfy-tags-cache}) with the 
'hfy-anchor property, with a value of "tag.line-number".

@item hfy-weight
@findex hfy-weight
@anchor{hfy-weight}

@lisp

(hfy-weight @var{weight})
@end lisp

Derive a font-weight css specifier from an emacs weight spec symbol.

@item hfy-size
@findex hfy-size
@anchor{hfy-size}

@lisp

(hfy-size @var{height})
@end lisp

Derive a css font-size specifier from an emacs font :height attribute.
Does not cope with the case where height is a function to be applied to
the height of the underlying font.

@item hfy-default-header
@findex hfy-default-header
@anchor{hfy-default-header}

@lisp

(hfy-default-header @var{file} @var{style})
@end lisp

Default value for @ref{hfy-page-header}

@item hfy-family
@findex hfy-family
@anchor{hfy-family}

@lisp

(hfy-family @var{family})
@end lisp

Derives a css font-family specifier from an emacs :family attribute.

@item hfy-mark-tag-hrefs
@findex hfy-mark-tag-hrefs
@anchor{hfy-mark-tag-hrefs}

@lisp

(hfy-mark-tag-hrefs @var{srcdir} @var{file})
@end lisp

Mark href start points with the 'hfy-link prop (value: href string)

Mark href end points with the 'hfy-endl prop (value t)

Avoid overlapping links, and mark links in descending length of
tag name in order to prevent subtags from usurping supertags,
(eg "term" for "terminal"). 

@item hfy-box
@findex hfy-box
@anchor{hfy-box}

@lisp

(hfy-box @var{box})
@end lisp

Derive CSS border-* attributes from the emacs :box attribute.

@item hfy-box-to-style
@findex hfy-box-to-style
@anchor{hfy-box-to-style}

@lisp

(hfy-box-to-style @var{spec})
@end lisp

Convert a complex :box emacs font attribute set to a list of CSS border-*
attributes. Don't call this directly - it is called by @ref{hfy-box}
when necessary.

@item hfy-html-enkludge-buffer
@findex hfy-html-enkludge-buffer
@anchor{hfy-html-enkludge-buffer}

@lisp

(hfy-html-enkludge-buffer)
@end lisp

Mark dangerous ["<>] characters with the 'hfy-quoteme property.

See also @ref{hfy-html-dekludge-buffer}.

@item hfy-buffer
@findex hfy-buffer
@anchor{hfy-buffer}

@lisp

(hfy-buffer)
@end lisp

Generate and return an htmlfontify html output buffer for the current 
buffer. May trample an existing buffer.

@item hfy-fontified-p
@findex hfy-fontified-p
@anchor{hfy-fontified-p}

@lisp

(hfy-fontified-p)
@end lisp

@code{font-lock} doesn't like to say a buffer's been fontified when in 
batch mode, but we want to know if we should fontify or raw copy, so in 
batch mode we check for non-default face properties. Otherwise we test
@code{font-lock-mode} and @code{font-lock-fontified} for truth.

@item hfy-lookup
@findex hfy-lookup
@anchor{hfy-lookup}

@lisp

(hfy-lookup @var{face} @var{style})
@end lisp

Where @var{style} is a @ref{hfy-sheet-assoc} and @var{face} is an emacs face, 
return the relevant @var{css} style name.

@item hfy-fontify-buffer
@findex hfy-fontify-buffer
@anchor{hfy-fontify-buffer}

@lisp

(hfy-fontify-buffer &optional @var{srcdir} @var{file})
@end lisp

Implement the guts of @ref{htmlfontify-buffer}

@item hfy-colour
@findex hfy-colour
@anchor{hfy-colour}

@lisp

(hfy-colour @var{colour})
@end lisp

Convert an emacs :foreground property to a CSS colour property.

@item hfy-flatten-style
@findex hfy-flatten-style
@anchor{hfy-flatten-style}

@lisp

(hfy-flatten-style @var{style})
@end lisp

Take @var{style} (see @ref{hfy-face-to-style-i}, @ref{hfy-face-to-style}) 
and merge any multiple attributes appropriately. Currently only font-size is 
merged down to a single occurrence - others may need special handling, but I
haven't encountered them yet. Returns a @ref{hfy-style-assoc}.

@item hfy-size-to-int
@findex hfy-size-to-int
@anchor{hfy-size-to-int}

@lisp

(hfy-size-to-int @var{spec})
@end lisp

Convert @var{spec}, a css font-size specifier, back to an emacs :height attribute
value. Used while merging multiple font-size attributes.

@item hfy-sprintf-stylesheet
@findex hfy-sprintf-stylesheet
@anchor{hfy-sprintf-stylesheet}

@lisp

(hfy-sprintf-stylesheet @var{css} @var{file})
@end lisp

Generates a header, via @ref{hfy-page-header}, for @var{file}, containing the 
stylesheet derived from @var{css}, which is a @ref{hfy-sheet-assoc}. Returns a 
string containing the same.

@item hfy-relstub
@findex hfy-relstub
@anchor{hfy-relstub}

@lisp

(hfy-relstub @var{file} &optional @var{start})
@end lisp

Return a "../" stub of the appropriate length for the current source
tree depth (as determined from @var{file}). iyswim.

@item hfy-compile-face-map
@findex hfy-compile-face-map
@anchor{hfy-compile-face-map}

@lisp

(hfy-compile-face-map)
@end lisp

Compile and return a @ref{hfy-facemap-assoc} for the current buffer.

@item hfy-prepare-index
@findex hfy-prepare-index
@anchor{hfy-prepare-index}

@lisp

(hfy-prepare-index @var{srcdir} @var{dstdir})
@end lisp

Return as list of index buffer(s), as determined by @ref{hfy-split-index}.
Uses @ref{hfy-prepare-index-i} to do this.

@item hfy-prepare-tag-map
@findex hfy-prepare-tag-map
@anchor{hfy-prepare-tag-map}

@lisp

(hfy-prepare-tag-map @var{srcdir} @var{dstdir})
@end lisp

Prepare the counterpart(s) to the index buffer(s) - a list of buffers with 
the same structure, but listing ( and linking to ) instances of tags ( as 
opposed to their definitions ).

See also: @ref{hfy-prepare-index}, @ref{hfy-split-index}

@item hfy-subtract-maps
@findex hfy-subtract-maps
@anchor{hfy-subtract-maps}

@lisp

(hfy-subtract-maps @var{srcdir})
@end lisp

Internal function - strips definitions of tags from the instance map.
See: @ref{hfy-tags-cache} and @ref{hfy-tags-rmap}

@item hfy-face-to-style-i
@findex hfy-face-to-style-i
@anchor{hfy-face-to-style-i}

@lisp

(hfy-face-to-style-i @var{fn})
@end lisp

The guts of @ref{hfy-face-to-style}: @var{fn} should be a @code{defface}
font specification, as returned by @code{face-attr-construct} or 
@ref{hfy-face-attr-for-class}. Note that this function does not get 
font-sizes right if they are based on inherited modifiers (via the 
:inherit) attribute, and any other modifiers that are cumulative if they 
appear multiple times need to be merged by the user - @ref{hfy-flatten-style} 
should do this.

@item hfy-face-to-css
@findex hfy-face-to-css
@anchor{hfy-face-to-css}

@lisp

(hfy-face-to-css @var{fn})
@end lisp

Take @var{fn}, a font or @code{defface} specification (cf. 
@code{face-attr-construct}) and return a CSS style specification.

See also: @ref{hfy-face-to-style}

@item hfy-html-quote
@findex hfy-html-quote
@anchor{hfy-html-quote}

@lisp

(hfy-html-quote @var{char-string})
@end lisp

Map a string (usu. 1 char long) to an html safe string (entity) if need be.

@item hfy-link-style
@findex hfy-link-style
@anchor{hfy-link-style}

@lisp

(hfy-link-style @var{style-string})
@end lisp

Convert the CSS style spec @var{style-string} to it's equivalent 
hyperlink style.

See: @ref{hfy-link-style-fun}.

@item hfy-p-to-face
@findex hfy-p-to-face
@anchor{hfy-p-to-face}

@lisp

(hfy-p-to-face @var{props})
@end lisp

Given @var{props}, a list of text-properties, return the value of the 
face property, or nil.

@item hfy-box-to-border-assoc
@findex hfy-box-to-border-assoc
@anchor{hfy-box-to-border-assoc}

@lisp

(hfy-box-to-border-assoc @var{spec})
@end lisp

Helper function for @ref{hfy-box-to-style}.

@item hfy-face-attr-for-class
@findex hfy-face-attr-for-class
@anchor{hfy-face-attr-for-class}

@lisp

(hfy-face-attr-for-class @var{face} &optional @var{class})
@end lisp

Return the face attributes for @var{face}. If @var{class} is set, it 
must be a @code{defface} alist key [see below]. Prior to version 0.18, 
the first face specification returned by @ref{hfy-combined-face-spec} 
which @emph{didn't} clash with @var{class} was returned. In versions 
from 0.18 onwards, each font attribute list is scored, and the 
non-conflicting list with the highest score is returned. ( A specification 
with a class of @code{t} is considered to match any class you specify: 
This matches emacs' behaviour when deciding on which face attributes to 
use, to the best of my understanding ).

If @var{class} is nil, then you just get get whatever 
@code{face-attr-construct} returns, ie the current specification in 
effect for @var{face}.

See @ref{hfy-display-class} for details of valid values for @var{class}.

@item hfy-face-at
@findex hfy-face-at
@anchor{hfy-face-at}

@lisp

(hfy-face-at P)
@end lisp

Find face in effect at point P. If overlays are to be considered
(see @ref{hfy-optimisations}) then this may return a @code{defface} style
list of face properties instead of a face symbol.

@item hfy-bgcol
@findex hfy-bgcol
@anchor{hfy-bgcol}

@lisp

(hfy-bgcol @var{colour})
@end lisp

As per @ref{hfy-colour} but for background colours.

@item hfy-kludge-cperl-mode
@findex hfy-kludge-cperl-mode
@anchor{hfy-kludge-cperl-mode}

@lisp

(hfy-kludge-cperl-mode)
@end lisp

cperl mode does its damndest not to do some of its fontification when not
in a windowing system - we try to trick it...

@item hfy-href
@findex hfy-href
@anchor{hfy-href}

@lisp

(hfy-href @var{this-file} @var{def-files} @var{tag} @var{tag-map})
@end lisp

Return a relative href to the tag in question, based on

@var{this-file} @ref{hfy-link-extn} @ref{hfy-extn} @var{def-files} @var{tag} and @var{tag-map}

@var{this-file} is the current source file
@var{def-files} is a list of file containing possible link endpoints for @var{tag}
@var{tag} is the @var{tag} in question
@var{tag-map} is the entry in @ref{hfy-tags-cache}.

@item hfy-shell
@findex hfy-shell
@anchor{hfy-shell}

@lisp

(hfy-shell)
@end lisp

Returns a best guess at a bourne compatible shell to use: If the current 
shell doesn't look promising, fall back to @ref{hfy-shell-file-name}.

@item hfy-load-tags-cache
@findex hfy-load-tags-cache
@anchor{hfy-load-tags-cache}

@lisp

(hfy-load-tags-cache @var{srcdir})
@end lisp

Run @ref{hfy-etags-cmd} on @var{srcdir}: load @ref{hfy-tags-cache} and @ref{hfy-tags-sortl}.

@item hfy-parse-tags-buffer
@findex hfy-parse-tags-buffer
@anchor{hfy-parse-tags-buffer}

@lisp

(hfy-parse-tags-buffer @var{srcdir} @var{buffer})
@end lisp

Parse a @var{buffer} containing etags formatted output, loading the
@ref{hfy-tags-cache} and @ref{hfy-tags-sortl} entries for @var{srcdir}.

@item hfy-interq
@findex hfy-interq
@anchor{hfy-interq}

@lisp

(hfy-interq @var{set-a} @var{set-b})
@end lisp

Return the intersection ( using @code{eq} ) of 2 lists.

@item hfy-text-p
@findex hfy-text-p
@anchor{hfy-text-p}

@lisp

(hfy-text-p @var{srcdir} @var{file})
@end lisp

Is @var{srcdir}/@var{file} text? Uses @ref{hfy-istext-command} to determine this.

@item hfy-opt
@findex hfy-opt
@anchor{hfy-opt}

@lisp

(hfy-opt @var{symbol})
@end lisp

Is @ref{hfy-optimisations} member @var{symbol} set or not?

@item hfy-dirname
@findex hfy-dirname
@anchor{hfy-dirname}

@lisp

(hfy-dirname @var{file})
@end lisp

Return everything preceding the last "/" from a relative filename,
on the assumption that this will produce a relative directory name. Hardly
bombproof, but good enough in the context in which it is being used.

@item hfy-html-dekludge-buffer
@findex hfy-html-dekludge-buffer
@anchor{hfy-html-dekludge-buffer}

@lisp

(hfy-html-dekludge-buffer)
@end lisp

Transform all dangerous characters marked with the 'hfy-quoteme property
using @ref{hfy-html-quote}

See also @ref{hfy-html-enkludge-buffer}.

@item hfy-copy-and-fontify-file
@findex hfy-copy-and-fontify-file
@anchor{hfy-copy-and-fontify-file}

@lisp

(hfy-copy-and-fontify-file @var{srcdir} @var{dstdir} @var{file})
@end lisp

open @var{file} in @var{srcdir} - if fontified, write a fontified copy to @var{dstdir}
adding an extension of @ref{hfy-extn}. Fontification is actually done by
@ref{htmlfontify-buffer}. If the buffer is not fontified, just copy it.

@item hfy-decor
@findex hfy-decor
@anchor{hfy-decor}

@lisp

(hfy-decor @var{tag} @var{val})
@end lisp

Derive CSS text-decoration specifiers from various emacs font attributes.

@item hfy-slant
@findex hfy-slant
@anchor{hfy-slant}

@lisp

(hfy-slant @var{slant})
@end lisp

Derive a font-style css specifier from the emacs :slant attribute -
CSS does not define the reverse-* styles, so just maps those to the
regular specifiers.

@item hfy-tags-for-file
@findex hfy-tags-for-file
@anchor{hfy-tags-for-file}

@lisp

(hfy-tags-for-file @var{srcdir} @var{file})
@end lisp

List of etags tags that have definitions in this @var{file}. Looks up
the tags cache in @ref{hfy-tags-cache} using @var{srcdir} as the key.

@item hfy-width
@findex hfy-width
@anchor{hfy-width}

@lisp

(hfy-width @var{width})
@end lisp

Convert an emacs :width attribute to a CSS font-stretch attribute.

@comment /AUTOGENERATED BLOCK
@end table

@node Variables, Data Structures, Non-interactive, Usage & Examples
@section Variables
@cindex variables

Important variables which are not customisation items:

@table @code

@item hfy-tags-cache
@vindex hfy-tags-cache
@anchor{hfy-tags-cache}

This is an alist of the form:

@example
(("/src/dir/0" . tag-hash0) ("/src/dir/1" tag-hash1) ...)
@end example

Each tag hash entry then contains entries of the form:

@example
"tag_string" => (("file/name.ext" line char) ... )
@end example

ie an alist mapping (relative) file paths to line and character offsets.

See @ref{hfy-load-tags-cache}.

@item hfy-tags-rmap
@vindex hfy-tags-rmap
@anchor{hfy-tags-rmap}

@code{hfy-tags-rmap} is an alist of the form:

@lisp
(("/src/dir" . tag-rmap-hash))
@end lisp

Where tag-rmap-hash has entries of the form:

@example
"tag_string" => ( "file/name.ext" line char )
@end example

Unlike @ref{hfy-tags-cache} these are the locations of occurrences of
tagged items, not the locations of their definitions.

@item hfy-tags-sortl
@vindex hfy-tags-sortl
@anchor{hfy-tags-sortl}

@code{hfy-tags-sortl} is an alist of the form:

@example
(("/src/dir" . (tag0 tag1 tag2)) ... )
@end example

Where the tags are stored in descending order of length.

See: @ref{hfy-load-tags-cache}.

@end table

@node Data Structures, Examples, Variables, Usage & Examples
@section Data Structures
@cindex Data Structures

Some of the (informal) data structures used in Htmlfontify are detailed here:

@table @code

@item hfy-style-assoc
@cindex hfy-style-assoc
@anchor{hfy-style-assoc}

An assoc representing/describing an emacs face. Properties may be repeated,
In which case later properties should be treated as if they were inherited
from a 'parent' font. (For some properties, only the first encountered value
is of any importance, for others the values might be cumulative, and for
others they might be cumulative in a complex way).

Some examples:

@lisp
(hfy-face-to-style 'default) =>

  (("background"      . "rgb(0, 0, 0)"      )
   ("color"           . "rgb(255, 255, 255)")
   ("font-style"      . "normal"            )
   ("font-weight"     . "500"               )
   ("font-stretch"    . "normal"            )
   ("font-family"     . "misc-fixed"        )
   ("font-size"       . "13pt"              )
   ("text-decoration" . "none"              ))

(hfy-face-to-style 'Info-title-3-face) =>

  (("font-weight"     . "700"        )
   ("font-family"     . "helv"       )
   ("font-size"       . "120%"       )
   ("text-decoration" . "none")      )
@end lisp

@item hfy-sheet-assoc
@cindex hfy-sheet-assoc
@anchor{hfy-sheet-assoc}

An assoc with elements of the form (face-name style-name . stlye-string):
The actual stylesheet for each page is derived from one of these.

@lisp
'((default       "default" . "@{ background: black; color: white@}")
  (font-lock-string-face "string"  . "@{ color: rgb(64,224,208) @}"))
@end lisp

@item hfy-facemap-assoc 
@cindex hfy-facemap-assoc
@anchor{hfy-facemap-assoc}

An assoc of (point . @var{face-symbol}) or 
(point . @code{defface} attribute list) and (point . 'end) elements, in
descending order of point value (ie from the file's end to its beginning).
The map is in reverse order because inserting a <style> tag (or any other
string) at @var{point} invalidates the map for all entries with a greater 
value of point. By traversing the map from greatest to least @var{point}, 
we still invalidate the map as we go, but only those points we have already 
dealt with ( and therefore no longer care about ) will be invalid at any 
time.

@lisp
'((64820 . end)
  (64744 . font-lock-comment-face)
  (64736 . end)
  (64722 . font-lock-string-face)
  (64630 . end)
  (64623 . font-lock-string-face)
  (64449 . end)
  ;; big similar section elided. You get the idea.
  (5459 . end)
  (5431 . (:inherit font-lock-keyword-face :background "7e7e7e"))
  (5431 . end)
  (4285 . font-lock-constant-face)
  (4285 . end)
  (4221 . font-lock-comment-face)
  (4221 . end)
  (4197 . font-lock-constant-face)
  (4197 . end)
  (1 . font-lock-comment-face))
@end lisp

@end table

@node Examples, , Data Structures, Usage & Examples
@section Examples
@cindex Examples

The following is a lump of code I use to fontify source code on my 
site, @url{http://rtfm.etla.org/} ( which was the reason, incidentally, 
that htmlfontify was written in the first place ).

@lisp
(defvar rtfm-section nil)

;; constructs an appropriate header string to fit in with rtfm's 
;; templating system, based on the file and the stylesheet string
(defun rtfm-build-page-header (file style)
  (format "#define  TEMPLATE red+black.html
#define  DEBUG    1
#include <build/menu-dirlist|>\n
html-css-url := /css/red+black.css
title        := rtfm.etla.org ( %s / src/%s )
bodytag      := 
head         <=STYLESHEET;\n
%s
STYLESHEET
main-title   := rtfm / %s / src/%s\n
main-content <=MAIN_CONTENT;\n" rtfm-section file style rtfm-section file))

;; the footer:
(defun rtfm-build-page-footer (file) "\nMAIN_CONTENT\n")

(defun rtfm-fontify-buffer (section)
  (interactive "s section[eg- emacs / p4-blame]: ")
  (require 'htmlfontify)
  (let ((hfy-page-header  'rtfm-build-page-header)
        (hfy-page-footer  'rtfm-build-page-footer)
        (rtfm-section                     section))
    (htmlfontify-buffer)
    )
  )

;; here's the function I catually call - it asks me for a section label, 
;; and source and destination directories, and then binds a couple of
;; customisation variable in a let before calling htmlfontify:
(defun rtfm-build-source-docs (section srcdir destdir)
  (interactive
   "s section[eg- emacs / p4-blame]:\nD source-dir: \nD output-dir: ")
  (require 'htmlfontify)
  (hfy-load-tags-cache srcdir)
  (let ((hfy-page-header  'rtfm-build-page-header)
        (hfy-page-footer  'rtfm-build-page-footer)
        (rtfm-section                     section)
        (hfy-index-file                   "index")
        (auto-mode-alist (append auto-mode-alist
                                 '(("dbi\\(shell\\|gtk\\)$" . cperl-mode)
                                   ("\\.xpm$"               . c-mode    ))))
        )
    (htmlfontify-run-etags srcdir)
    (htmlfontify-copy-and-link-dir srcdir destdir ".src" ".html")))
@end lisp

@node Customisation, Requirements, Usage & Examples, Top
@chapter Customisation
@cindex variables (customisation)

Htmlfontify provides the following variable and customisation entries:

@table @code
@comment  AUTOGENERATED BLOCK

@item hfy-link-style-fun
@vindex hfy-link-style-fun
@anchor{hfy-link-style-fun}

Set this to a function, which will be called with one argument
(a "@{ foo: bar; ...@}" css style-string) - it should return a copy of
its argument, altered so as to make any changes you want made for text which
is a hyperlink, in addition to being in the class to which that style would
normally be applied.

@item hfy-html-quote-regex
@vindex hfy-html-quote-regex
@anchor{hfy-html-quote-regex}

Regex to match (with a single back-reference per match) strings in HTML
which should be quoted with @ref{hfy-html-quote} 
(and @pxref{hfy-html-quote-map}) to make them safe.

@item hfy-page-footer
@vindex hfy-page-footer
@anchor{hfy-page-footer}

As @ref{hfy-page-header}, but generates the output footer
(and takes only 1 argument, the filename).

@item hfy-display-class
@vindex hfy-display-class
@anchor{hfy-display-class}

Display class to use to determine which display class to use when
calculating a face's attributes. This is useful when, for example, you
are running emacs on a tty or in batch mode, and want htmlfontify to have
access to the face spec you would use if you were connected to an X display.

Some valid class specification elements are:

@lisp
  '(class      color)
  '(class      grayscale)
  '(background dark)
  '(background light)
  '(type       x-toolkit)
  '(type       tty)
  '(type       motif)
  '(type       lucid)
@end lisp

Multiple values for a tag may be combined, to indicate that any one or more
of these values in the specification key constitutes a match, eg:

'((class color grayscale) (type tty)) would match any of:
@lisp
  '((class color))
  '((class grayscale))
  '((class color grayscale)))
  '((class color foo))
  '((type  tty))
  '((type  tty) (class color))
@end lisp
and so on.

@item hfy-page-header
@vindex hfy-page-header
@anchor{hfy-page-header}

Function called with two arguments (the filename relative to the top
level source directory being etag'd and fontified), and a string containing
the <style>...</style> text to embed in the document- the string returned will
be used as the header for the htmlfontified version of the source file.

See also: @ref{hfy-page-footer}

@item hfy-src-doc-link-style
@vindex hfy-src-doc-link-style
@anchor{hfy-src-doc-link-style}

String to add to the '<style> a' variant of an htmlfontify css class.

@item hfy-fast-lock-save
@vindex hfy-fast-lock-save
@anchor{hfy-fast-lock-save}

Minimum size of a buffer for cached fontification.
This value is temporarily assigned to @code{fast-lock-minimum-size} during
html-fontification.

Only buffers more than this can have associated Font Lock cache files saved.

If nil, means cache files are never created.

If a list, each element should be a cons pair of the form 
@code{(@var{major-mode} . @var{size})}, where @var{major-mode} 
is a symbol or t (meaning the default).  For example:

@lisp
 ((c-mode     . 25600  )
  (c++-mode   . 25600  )
  (rmail-mode . 1048576))
@end lisp

means that the minimum size is 25K for buffers in C or C++ modes, one megabyte
for buffers in Rmail mode, and size is irrelevant (ie no saves) otherwise.

@item hfy-split-index
@vindex hfy-split-index
@anchor{hfy-split-index}

Whether or not to split the index @ref{hfy-index-file} alphabetically
on the first letter of each tag. Useful when the index would otherwise
be large and take a long time to render or be difficult to navigate.

@item hfy-find-cmd
@vindex hfy-find-cmd
@anchor{hfy-find-cmd}

``find'' command used to harvest a list of files to attempt to fontify.

@item hfy-extn
@vindex hfy-extn
@anchor{hfy-extn}

File extension used for output files

@item hfy-default-face-def
@vindex hfy-default-face-def
@anchor{hfy-default-face-def}

Fallback @code{defface} specification for the face @code{default}, used 
when @ref{hfy-display-class} has been set ( the normal htmlfontify way of 
extracting potentially non-current face information doesn't necessarily 
work for @code{default} ).

Example: I customise this to:

@lisp
((t :background "black" :foreground "white" :family "misc-fixed"))
@end lisp

@item hfy-init-kludge-hooks
@vindex hfy-init-kludge-hooks
@anchor{hfy-init-kludge-hooks}

List of functions to call when starting htmlfontify-buffer to do any
kludging necessary to get highlighting modes to bahave as you want, even
when not running under a window system.

@item hfy-shell-file-name
@vindex hfy-shell-file-name
@anchor{hfy-shell-file-name}

Should be set to a bourne compatible shell, which will be invoked 
for the more complex shell interactions needed by htmlfontify.
Currently this is only required/used when using GNU etags, see 
@ref{hfy-etags-cmd-alist} for details.

@item hfy-optimisations
@vindex hfy-optimisations
@anchor{hfy-optimisations}

Optimisations to turn on: So far, the following have been implemented:

@table @option
@item merge-adjacent-tags
If two (or more) span tags are adjacent, identical and separated by nothing 
more than whitespace, they will be merged into one span.

@item zap-comment-links
Suppress hyperlinking of tags found in comments.

@item zap-string-links
Suppress hyperlinking of tags found in strings.

@item div-wrapper
Add <div class="default"> </div> tags around the fontified body.
( some people like this because they cut and paste the html into 
  a page with different colours than the fontified code. )

@item keep-overlays
preserve overlay highlighting (cf @code{ediff} or @code{goo-font-lock}) 
as well as basic faces. Can result in extremely verbose highlighting 
if there are many overlays (as is the case with @code{goo-font-lock}).

@end table

And the following are planned but not yet available:

@table @option
@item kill-context-leak
Suppress hyperlinking between files highlighted by different modes.

@end table

Note: like compiler optimisations, these optimise the _output_ of the code,
not the processing of the source itself, and are therefore likely to slow
htmlfontify down, at least a little. Except for skip-refontification,
which can never slow you down, but may result in incomplete fontification.

@item hfy-src-doc-link-unstyle
@vindex hfy-src-doc-link-unstyle
@anchor{hfy-src-doc-link-unstyle}

Regex to remove from the <style> a variant of an htmlfontify css class.

@item hfy-link-extn
@vindex hfy-link-extn
@anchor{hfy-link-extn}

File extension used for href links - Useful where the htmlfontify
output files are going to be processed again, with a rersulting change
in file extension. If @code{nil}, then any code using this should fall back
to @ref{hfy-extn}.

@item hfy-istext-command
@vindex hfy-istext-command
@anchor{hfy-istext-command}

Command to run with the name of a file, to see whether it is a text file
or not. The command should emit a string containing the word 'text' if
the file is a text file, and a string not containing 'text' otherwise.

@item hfy-etags-cmd-alist
@vindex hfy-etags-cmd-alist
@anchor{hfy-etags-cmd-alist}

An alist of possible shell commands that will generate etags output that
Htmlfontify can use. '%s' will be replaced by @ref{hfy-etags-bin}.

@item hfy-etags-bin
@vindex hfy-etags-bin
@anchor{hfy-etags-bin}

The Location of the etags binary (we begin by assuming it's in your path).

Note that if etags is not in your path, you will need to alter the shell
commands in @ref{hfy-etags-cmd-alist}.

[ As of version 0.17, this requirement has been removed: It should 
  all just work(tm) ]

@item hfy-etags-cmd
@vindex hfy-etags-cmd
@anchor{hfy-etags-cmd}

An etags shell command to run in the source directory to generate a tags
file for the whole source tree from there on down. The command should emit
the etags output on standard output.

Two canned commands are provided - they drive emacs' etags and
exuberant-ctags' etags respectively.

@item hfy-etag-regex
@vindex hfy-etag-regex
@anchor{hfy-etag-regex}

Regex used to parse an etags entry: must have 3 subexps, corresponding,
in order, to:

@enumerate
   The tag
   The line
   The char (point) at which the tag occurs
@end enumerate

@item hfy-index-file
@vindex hfy-index-file
@anchor{hfy-index-file}

Name (sans extension) of the index file produced during 
fontification-and-hyperlinking.

@item hfy-instance-file
@vindex hfy-instance-file
@anchor{hfy-instance-file}

Name (sans extension) of the tag usage index file produced during
fontification-and-hyperlinking.

@item hfy-html-quote-map
@vindex hfy-html-quote-map
@anchor{hfy-html-quote-map}

An alist of char -> entity mappings used to make the text html-safe.

@comment /AUTOGENERATED BLOCK
@end table

@node Requirements, Index, Customisation, Top
@chapter Requirements
@cindex Requirements, Prerequisites

Htmlfontify has a couple of external requirements:

@itemize @bullet

@item
GNU Emacs 20.7+ or 21.1+

Other versions may work - these have been used successfully by the 
author. If you intend to use Htmlfontify in batch mode, 21.1+ is 
pretty much required. The author does not know if XEmacs, NTemacs, 
or J.Random Emacs will run Htmlfontify, but reports/patches/bags of 
money are always welcome.

@item 
A copy of etags ( exuberant-ctags or GNU etags ). Htmlfontify attempts 
to autodetect the version you have and customise itself accordingly, 
but you should be able to override this. 

See: @ref{Customisation}

@item
A copy of find (eg GNU find) that provides the @code{-path} predicate.

You may be able to work around this with a suitable clever shell
command and the customisation entry: @ref{hfy-find-cmd}

@item 
A copy of sed (eg GNU sed).

@item
A copy of the @code{file} command.

@end itemize

@node Index,  , Requirements, Top
@unnumbered Index

@table @var
@item Concepts
@printindex cp

@item Functions
@printindex fn

@item Variables & Customisation
@printindex vr

@end table

@node COPYING, , , Top
@appendix GNU Free Documentation Licence

@cindex FDL, GNU Free Documentation License
@center Version 1.1, March 2000

@display
Copyright @copyright{} 2000 Free Software Foundation, Inc.
59 Temple Place, Suite 330, Boston, MA  02111-1307, USA

Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
@end display

@enumerate 0
@item
PREAMBLE

The purpose of this License is to make a manual, textbook, or other
written document @dfn{free} in the sense of freedom: to assure everyone
the effective freedom to copy and redistribute it, with or without
modifying it, either commercially or noncommercially.  Secondarily,
this License preserves for the author and publisher a way to get
credit for their work, while not being considered responsible for
modifications made by others.

This License is a kind of ``copyleft'', which means that derivative
works of the document must themselves be free in the same sense.  It
complements the GNU General Public License, which is a copyleft
license designed for free software.

We have designed this License in order to use it for manuals for free
software, because free software needs free documentation: a free
program should come with manuals providing the same freedoms that the
software does.  But this License is not limited to software manuals;
it can be used for any textual work, regardless of subject matter or
whether it is published as a printed book.  We recommend this License
principally for works whose purpose is instruction or reference.

@item
APPLICABILITY AND DEFINITIONS

This License applies to any manual or other work that contains a
notice placed by the copyright holder saying it can be distributed
under the terms of this License.  The ``Document'', below, refers to any
such manual or work.  Any member of the public is a licensee, and is
addressed as ``you''.

A ``Modified Version'' of the Document means any work containing the
Document or a portion of it, either copied verbatim, or with
modifications and/or translated into another language.

A ``Secondary Section'' is a named appendix or a front-matter section of
the Document that deals exclusively with the relationship of the
publishers or authors of the Document to the Document's overall subject
(or to related matters) and contains nothing that could fall directly
within that overall subject.  (For example, if the Document is in part a
textbook of mathematics, a Secondary Section may not explain any
mathematics.)  The relationship could be a matter of historical
connection with the subject or with related matters, or of legal,
commercial, philosophical, ethical or political position regarding
them.

The ``Invariant Sections'' are certain Secondary Sections whose titles
are designated, as being those of Invariant Sections, in the notice
that says that the Document is released under this License.

The ``Cover Texts'' are certain short passages of text that are listed,
as Front-Cover Texts or Back-Cover Texts, in the notice that says that
the Document is released under this License.

A ``Transparent'' copy of the Document means a machine-readable copy,
represented in a format whose specification is available to the
general public, whose contents can be viewed and edited directly and
straightforwardly with generic text editors or (for images composed of
pixels) generic paint programs or (for drawings) some widely available
drawing editor, and that is suitable for input to text formatters or
for automatic translation to a variety of formats suitable for input
to text formatters.  A copy made in an otherwise Transparent file
format whose markup has been designed to thwart or discourage
subsequent modification by readers is not Transparent.  A copy that is
not ``Transparent'' is called ``Opaque''.

Examples of suitable formats for Transparent copies include plain
@sc{ascii} without markup, Texinfo input format, La@TeX{} input format,
@acronym{SGML} or @acronym{XML} using a publicly available
@acronym{DTD}, and standard-conforming simple @acronym{HTML} designed
for human modification.  Opaque formats include PostScript,
@acronym{PDF}, proprietary formats that can be read and edited only by
proprietary word processors, @acronym{SGML} or @acronym{XML} for which
the @acronym{DTD} and/or processing tools are not generally available,
and the machine-generated @acronym{HTML} produced by some word
processors for output purposes only.

The ``Title Page'' means, for a printed book, the title page itself,
plus such following pages as are needed to hold, legibly, the material
this License requires to appear in the title page.  For works in
formats which do not have any title page as such, ``Title Page'' means
the text near the most prominent appearance of the work's title,
preceding the beginning of the body of the text.

@item
VERBATIM COPYING

You may copy and distribute the Document in any medium, either
commercially or noncommercially, provided that this License, the
copyright notices, and the license notice saying this License applies
to the Document are reproduced in all copies, and that you add no other
conditions whatsoever to those of this License.  You may not use
technical measures to obstruct or control the reading or further
copying of the copies you make or distribute.  However, you may accept
compensation in exchange for copies.  If you distribute a large enough
number of copies you must also follow the conditions in section 3.

You may also lend copies, under the same conditions stated above, and
you may publicly display copies.

@item
COPYING IN QUANTITY

If you publish printed copies of the Document numbering more than 100,
and the Document's license notice requires Cover Texts, you must enclose
the copies in covers that carry, clearly and legibly, all these Cover
Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on
the back cover.  Both covers must also clearly and legibly identify
you as the publisher of these copies.  The front cover must present
the full title with all words of the title equally prominent and
visible.  You may add other material on the covers in addition.
Copying with changes limited to the covers, as long as they preserve
the title of the Document and satisfy these conditions, can be treated
as verbatim copying in other respects.

If the required texts for either cover are too voluminous to fit
legibly, you should put the first ones listed (as many as fit
reasonably) on the actual cover, and continue the rest onto adjacent
pages.

If you publish or distribute Opaque copies of the Document numbering
more than 100, you must either include a machine-readable Transparent
copy along with each Opaque copy, or state in or with each Opaque copy
a publicly-accessible computer-network location containing a complete
Transparent copy of the Document, free of added material, which the
general network-using public has access to download anonymously at no
charge using public-standard network protocols.  If you use the latter
option, you must take reasonably prudent steps, when you begin
distribution of Opaque copies in quantity, to ensure that this
Transparent copy will remain thus accessible at the stated location
until at least one year after the last time you distribute an Opaque
copy (directly or through your agents or retailers) of that edition to
the public.

It is requested, but not required, that you contact the authors of the
Document well before redistributing any large number of copies, to give
them a chance to provide you with an updated version of the Document.

@item
MODIFICATIONS

You may copy and distribute a Modified Version of the Document under
the conditions of sections 2 and 3 above, provided that you release
the Modified Version under precisely this License, with the Modified
Version filling the role of the Document, thus licensing distribution
and modification of the Modified Version to whoever possesses a copy
of it.  In addition, you must do these things in the Modified Version:

@enumerate A
@item
Use in the Title Page (and on the covers, if any) a title distinct
from that of the Document, and from those of previous versions
(which should, if there were any, be listed in the History section
of the Document).  You may use the same title as a previous version
if the original publisher of that version gives permission.

@item
List on the Title Page, as authors, one or more persons or entities
responsible for authorship of the modifications in the Modified
Version, together with at least five of the principal authors of the
Document (all of its principal authors, if it has less than five).

@item
State on the Title page the name of the publisher of the
Modified Version, as the publisher.

@item
Preserve all the copyright notices of the Document.

@item
Add an appropriate copyright notice for your modifications
adjacent to the other copyright notices.

@item
Include, immediately after the copyright notices, a license notice
giving the public permission to use the Modified Version under the
terms of this License, in the form shown in the Addendum below.

@item
Preserve in that license notice the full lists of Invariant Sections
and required Cover Texts given in the Document's license notice.

@item
Include an unaltered copy of this License.

@item
Preserve the section entitled ``History'', and its title, and add to
it an item stating at least the title, year, new authors, and
publisher of the Modified Version as given on the Title Page.  If
there is no section entitled ``History'' in the Document, create one
stating the title, year, authors, and publisher of the Document as
given on its Title Page, then add an item describing the Modified
Version as stated in the previous sentence.

@item
Preserve the network location, if any, given in the Document for
public access to a Transparent copy of the Document, and likewise
the network locations given in the Document for previous versions
it was based on.  These may be placed in the ``History'' section.
You may omit a network location for a work that was published at
least four years before the Document itself, or if the original
publisher of the version it refers to gives permission.

@item
In any section entitled ``Acknowledgments'' or ``Dedications'',
preserve the section's title, and preserve in the section all the
substance and tone of each of the contributor acknowledgments
and/or dedications given therein.

@item
Preserve all the Invariant Sections of the Document,
unaltered in their text and in their titles.  Section numbers
or the equivalent are not considered part of the section titles.

@item
Delete any section entitled ``Endorsements''.  Such a section
may not be included in the Modified Version.

@item
Do not retitle any existing section as ``Endorsements''
or to conflict in title with any Invariant Section.
@end enumerate

If the Modified Version includes new front-matter sections or
appendices that qualify as Secondary Sections and contain no material
copied from the Document, you may at your option designate some or all
of these sections as invariant.  To do this, add their titles to the
list of Invariant Sections in the Modified Version's license notice.
These titles must be distinct from any other section titles.

You may add a section entitled ``Endorsements'', provided it contains
nothing but endorsements of your Modified Version by various
parties---for example, statements of peer review or that the text has
been approved by an organization as the authoritative definition of a
standard.

You may add a passage of up to five words as a Front-Cover Text, and a
passage of up to 25 words as a Back-Cover Text, to the end of the list
of Cover Texts in the Modified Version.  Only one passage of
Front-Cover Text and one of Back-Cover Text may be added by (or
through arrangements made by) any one entity.  If the Document already
includes a cover text for the same cover, previously added by you or
by arrangement made by the same entity you are acting on behalf of,
you may not add another; but you may replace the old one, on explicit
permission from the previous publisher that added the old one.

The author(s) and publisher(s) of the Document do not by this License
give permission to use their names for publicity for or to assert or
imply endorsement of any Modified Version.

@item
COMBINING DOCUMENTS

You may combine the Document with other documents released under this
License, under the terms defined in section 4 above for modified
versions, provided that you include in the combination all of the
Invariant Sections of all of the original documents, unmodified, and
list them all as Invariant Sections of your combined work in its
license notice.

The combined work need only contain one copy of this License, and
multiple identical Invariant Sections may be replaced with a single
copy.  If there are multiple Invariant Sections with the same name but
different contents, make the title of each such section unique by
adding at the end of it, in parentheses, the name of the original
author or publisher of that section if known, or else a unique number.
Make the same adjustment to the section titles in the list of
Invariant Sections in the license notice of the combined work.

In the combination, you must combine any sections entitled ``History''
in the various original documents, forming one section entitled
``History''; likewise combine any sections entitled ``Acknowledgments'',
and any sections entitled ``Dedications''.  You must delete all sections
entitled ``Endorsements.''

@item
COLLECTIONS OF DOCUMENTS

You may make a collection consisting of the Document and other documents
released under this License, and replace the individual copies of this
License in the various documents with a single copy that is included in
the collection, provided that you follow the rules of this License for
verbatim copying of each of the documents in all other respects.

You may extract a single document from such a collection, and distribute
it individually under this License, provided you insert a copy of this
License into the extracted document, and follow this License in all
other respects regarding verbatim copying of that document.

@item
AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other separate
and independent documents or works, in or on a volume of a storage or
distribution medium, does not as a whole count as a Modified Version
of the Document, provided no compilation copyright is claimed for the
compilation.  Such a compilation is called an ``aggregate'', and this
License does not apply to the other self-contained works thus compiled
with the Document, on account of their being thus compiled, if they
are not themselves derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these
copies of the Document, then if the Document is less than one quarter
of the entire aggregate, the Document's Cover Texts may be placed on
covers that surround only the Document within the aggregate.
Otherwise they must appear on covers around the whole aggregate.

@item
TRANSLATION

Translation is considered a kind of modification, so you may
distribute translations of the Document under the terms of section 4.
Replacing Invariant Sections with translations requires special
permission from their copyright holders, but you may include
translations of some or all Invariant Sections in addition to the
original versions of these Invariant Sections.  You may include a
translation of this License provided that you also include the
original English version of this License.  In case of a disagreement
between the translation and the original English version of this
License, the original English version will prevail.

@item
TERMINATION

You may not copy, modify, sublicense, or distribute the Document except
as expressly provided for under this License.  Any other attempt to
copy, modify, sublicense or distribute the Document is void, and will
automatically terminate your rights under this License.  However,
parties who have received copies, or rights, from you under this
License will not have their licenses terminated so long as such
parties remain in full compliance.

@item
FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions
of the GNU Free Documentation License from time to time.  Such new
versions will be similar in spirit to the present version, but may
differ in detail to address new problems or concerns.  See
@uref{http://www.gnu.org/copyleft/}.

Each version of the License is given a distinguishing version number.
If the Document specifies that a particular numbered version of this
License ``or any later version'' applies to it, you have the option of
following the terms and conditions either of that specified version or
of any later version that has been published (not as a draft) by the
Free Software Foundation.  If the Document does not specify a version
number of this License, you may choose any version ever published (not
as a draft) by the Free Software Foundation.
@end enumerate

@page
@appendixsubsec ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and
license notices just after the title page:

@smallexample
@group
  Copyright (C)  @var{year}  @var{your name}.
  Permission is granted to copy, distribute and/or modify this document
  under the terms of the GNU Free Documentation License, Version 1.1
  or any later version published by the Free Software Foundation;
  with the Invariant Sections being @var{list their titles}, with the
  Front-Cover Texts being @var{list}, and with the Back-Cover Texts being @var{list}.
  A copy of the license is included in the section entitled ``GNU
  Free Documentation License''.
@end group
@end smallexample

If you have no Invariant Sections, write ``with no Invariant Sections''
instead of saying which ones are invariant.  If you have no
Front-Cover Texts, write ``no Front-Cover Texts'' instead of
``Front-Cover Texts being @var{list}''; likewise for Back-Cover Texts.

If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of
free software license, such as the GNU General Public License,
to permit their use in free software.

@setchapternewpage odd
@contents
@bye