\input texinfo   @c -*-texinfo-*-
@setfilename zile.info
@settitle The Zile Manual

@dircategory Editors
@direntry
* Zile: (zile).                 A very small Emacs-subset editor.
@end direntry

@c If "finalout" is commented out, the printed output will show
@c black boxes that mark lines that are too long.  Thus, it is
@c unwise to comment it out when running a master in case there are
@c overfulls which are deemed okay.

@iftex
@c @finalout
@end iftex

@setchapternewpage odd

@titlepage
@title The Zile Manual
@subtitle for GNU Zile version 2.2
@subtitle April 2008
@author Sandro Sigala and Reuben Thomas

@page
@vskip 0pt plus 1filll
Copyright @copyright{} 2008 Free Software Foundation, Inc.

Copyright @copyright{} 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Sandro Sigala

Copyright @copyright{} 2003, 2004, 2005, 2006, 2007, 2008 Reuben Thomas

Copyright @copyright{} 2004 David A. Capello

Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.2 or
any later version published by the Free Software Foundation; with no
Invariant Sections, Front-Cover Texts or Back-Cover Texts.
A copy of the license is included in the section
entitled ``GNU Free Documentation License''.

@end titlepage

@c ---------------------------------------------------------------------------
@node Top, Overview, (dir), (dir)

This is the @emph{GNU Zile} manual.

GNU Zile is small Emacs clone.
Zile is a customizable, self-documenting real-time display editor.
Zile was written to be as similar as possible to Emacs; every Emacs
user should feel at home with Zile.

Zile's home page at @url{http://www.gnu.org/software/zile/}.

@menu
* Overview::                    An overview of the Zile editor.
* Features::                    The characteristics of Zile.
* Invoking Zile::               Command line options that you can give to Zile.
* Initialization file::         The ``.zile'' initialization file.
* Getting help::                How to get help in Zile.
* Key names::                   How the keys are named.
* Functions::                   The list of functions.
* Variables::                   The list of variables.
* Help and bug reports::        How to get help and report bugs.
* GNU Free Documentation License::  The GNU Free Documentation License.
@end menu

@c ---------------------------------------------------------------------------
@node Overview, Features, Top, Top
@chapter Overview

GNU Zile is written entirely in @emph{@w{ISO C89}}. It should run on any
POSIX system.

Zile should really appear like Emacs, but a lot of good ideas were
also taken from other editors; in particular, ce for the internal
structure.

@c ---------------------------------------------------------------------------
@node Features, Invoking Zile, Overview, Top
@chapter Features

@itemize -
@item Small but fast and powerful.
It is useful for small footprint installations (e.g. on floppy disk) and
small computers.
@item 8-bit clean.
Zile can operate with binary files.
@item Looks like @emph{Emacs}.
Key sequences and function names are identical to Emacs.
@item Multi buffer editing with multi level undo.
Zile can open as many files and restore as many undo operations as
memory allows.
@item Multi window.
Zile can display multiple windows on the screen.
@item Killing, yanking and registers.
The killing, yanking and register features of Emacs are available
in Zile.
@item Minibuffer completion.
This works for @kbd{M-x} commands, file, buffer and variable names.
@item Auto fill (word wrap).
Zile automatically breaks the lines when they become too wide (if
@i{Auto Fill Mode} is enabled).
@item Auto line ending detection.
When a file is loaded, its line ending is detected automatically as
either LF, CR or CRLF.  Files with mixed line endings will be displayed
as if they had LF line endings.  If a CR line ending is detected,
``(Mac)'' is shown in the modeline, and for CRLF, ``(DOS)''.
@end itemize

@c ---------------------------------------------------------------------------
@node Invoking Zile, Initialization file, Features, Top
@chapter Invoking Zile

The options are as follows:

@table @samp
@item FILE
Edit file @file{FILE}.
@item +NUMBER
Go to line @samp{NUMBER} in the next file opened.
@item --batch
Do not do interactive display; implies @samp{-q}.
@item --help
Display a help message and exit.
@item -f, --funcall FUNC
Call Zile function @samp{FUNC} with no arguments.
@item --no-init-file, -q
Do not load an init file.
@item --version
Display version information and exit.
@end table

Zile returns 0 on successful termination, 1 if it cannot start up, for
example because of an invalid command-line argument, and 2 if it
crashes or runs out of memory.

@c ---------------------------------------------------------------------------
@node Initialization file, Getting help, Invoking Zile, Top
@chapter Initialization file

When Zile is started, it normally loads the @file{.zile} file in your
home directory.  We call this file your ``initialization file'' because
it specifies how to initialize Zile for you.  You can use the command
line switch @samp{-q} to tell Zile not to load the initialization file.

@menu
* File syntax::                 The initialization file syntax.
* Sample file::                 A sample initialization file.
@end menu

@c ---------------------------------------------------------------------------
@node File syntax, Sample file, Initialization file, Initialization file
@section File syntax

The initialization file is written in Zile Lisp.  Zile Lisp is a tiny
subset of Emacs Lisp that consists of the Zile commands plus
@code{setq}.  See the next subsection for a sample initialization file.

@c ---------------------------------------------------------------------------
@node Sample file,  , File syntax, Initialization file
@section A sample file

This is an initialization file that shows the default variable settings.
You can use it as a model for your own init file.

@include dotzile.texi

@c ---------------------------------------------------------------------------
@node Getting help, Key names, Initialization file, Top
@chapter Getting help

This table contains the commands that can be used during an editing
session to get help.

@table @kbd
@item C-h C-f, @key{f1} C-f
Show the Frequently Asked Questions about Zile.
@item C-h f, @key{f1} f
Describe a function.
@item C-h h, @key{f1} h, @key{f1} @key{f1}
Show this manual.
@item C-h k, @key{f1} k
Describe a key sequence.
@item C-h b, @key{f1} b
Show the defined bindings.
@item C-h t, @key{f1} t
Show a tutorial window.
@item C-h v, @key{f1} v
Describe a variable.
@item C-h w, @key{f1} w
Show the key or keys to which a command is bound.
@end table

@c ---------------------------------------------------------------------------
@node Key names, Functions, Getting help, Top
@chapter Key names

This table contains the names of the keys that are used in Zile.

@table @key
@item SPC
Space
@item RET
Return
@item TAB
Tab
@item BACKSPACE
Backspace
@item ESC
Escape
@item DELETE
Delete
@item CTRL
Control
@item META
Meta (also known as @key{EDIT} or @key{ALT} on some keyboards).
@item PRIOR
PgUp (page up) (also called @key{PAGEUP}).
@item NEXT
PgDn (page down) (also called @key{PAGEDOWN}).
@end table

In key combinations, like @kbd{M-g}, the @kbd{M-} prefix means hold the
@key{META} (or @key{EDIT} or @key{ALT}) key down while typing @kbd{g}.
The combination @kbd{C-x} means hold the @key{CTRL} key down while
typing @kbd{x}.

@c ---------------------------------------------------------------------------
@node Functions, Variables, Key names, Top
@chapter Functions

This table contains the full list of available functions, that can be
called with the @kbd{M-x} key (most functions also have a key binding).

@c LINT FUNC
@table @code
@item auto-fill-mode
Toggle @i{Auto Fill Mode}.
In @i{Auto Fill Mode}, inserting a space at a column beyond @samp{fill-column}
automatically breaks the line at a previous space.
@item back-to-indentation
Move point to the first non-whitespace character on this line.
@item backward-char
Move point left one character.
On attempt to pass beginning or end of buffer, stop and signal error.
@item backward-delete-char
Delete the previous character.
Join lines if the character is a newline.
@item backward-kill-word
Kill characters backward until encountering the end of a word.
With argument, do this that many times.
@item backward-paragraph
Move backward to start of paragraph.  With argument N, do it N times.
@item backward-sexp
Move backward across one balanced expression (sexp).
With argument, do it that many times.  Negative arg -N means
move forward across N balanced expressions.
@item backward-word
Move backward until encountering the end of a word (forward if the
argument is negative).
With argument, do this that many times.
@item beginning-of-buffer
Move point to the beginning of the buffer; leave mark at previous position.
@item beginning-of-line
Move point to beginning of current line.
@item call-last-kbd-macro
Call the last keyboard macro that you defined with @kbd{C-x (}.
A prefix argument serves as a repeat count.
@item capitalize-word
Capitalize the following word (or argument N words), moving over.
This gives the word(s) a first character in upper case and the rest
lower case.
@item cd
Make the user specified directory become the current buffer's default
directory.
@item copy-region-as-kill
Save the region as if killed, but don't kill it.
@item copy-to-register
Copy region into the user specified register.
@item delete-blank-lines
On blank line, delete all surrounding blank lines, leaving just one.
On isolated blank line, delete that one.
On non-blank line, delete any immediately following blank lines.
@item delete-char
Delete the following character.
Join lines if the character is a newline.
@item delete-horizontal-space
Delete all spaces and tabs around point.
@item delete-other-windows
Make the selected window fill the screen.
@item delete-region
Delete the text between point and mark.
@item delete-window
Remove the current window from the screen.
@item describe-bindings
Show a list of all defined keys, and their definitions.
@item describe-function
Display the full documentation of a function.
@item describe-key
Display documentation of the function invoked by a key sequence.
@item describe-variable
Display the full documentation of a variable.
@item downcase-region
Convert the region to lower case.
@item downcase-word
Convert following word (or argument N words) to lower case, moving over.
@item end-kbd-macro
Finish defining a keyboard macro.
The definition was started by @kbd{C-x (}.
The macro is now available for use via @kbd{C-x e}.
@item end-of-buffer
Move point to the end of the buffer; leave mark at previous position.
@item end-of-line
Move point to end of current line.
@item enlarge-window
Make current window one line bigger.
@item exchange-point-and-mark
Put the mark where point is now, and point where the mark is now.
@item execute-extended-command
Read function name, then read its arguments and call it.
@item fill-paragraph
Fill paragraph at or after point.
@item find-alternate-file
Find the file specified by the user, select its buffer, kill previous buffer.
If the current buffer now contains an empty file that you just visited
(presumably by mistake), use this command to visit the file you really want.
@item find-file
Edit the specified file.
Switch to a buffer visiting the file,
creating one if none already exists.
@item find-file-read-only
Edit the specified file but don't allow changes.
Like `find-file' but marks buffer as read-only.
Use M-x toggle-read-only to permit editing.
@item forward-char
Move point right one character.
On reaching end of buffer, stop and signal error.
@item forward-line
Move N lines forward (backward if N is negative).
Precisely, if point is on line I, move to the start of line I + N.
@item forward-paragraph
Move forward to end of paragraph.  With argument N, do it N times.
@item forward-sexp
Move forward across one balanced expression (sexp).
With argument, do it that many times.  Negative arg -N means
move backward across N balanced expressions.
@item forward-word
Move point forward one word (backward if the argument is negative).
With argument, do this that many times.
@item global-set-key
Bind a command to a key sequence.
Read key sequence and function name, and bind the function to the key
sequence.
@item goto-char
Read a number N and move the cursor to character number N.
Position 1 is the beginning of the buffer.
@item goto-line
Move cursor to the beginning of the specified line.
Line 1 is the beginning of the buffer.
@item help
Show a help window.
@item help-with-tutorial
Show a tutorial.
@item indent-for-tab-command
Indent line or insert a tab.
Depending on @i{tab-always-indent}, either insert a tab or indent.
If initial point was within line's indentation, position after
the indentation.  Else stay at same point in text.
@item indent-relative
Space out to under next indent point in previous nonblank line.
An indent point is a non-whitespace character following whitespace.
If the previous nonblank line has no indent points beyond the
column point starts at, @i{tab-to-tab-stop} is done instead, unless
this command is invoked with a numeric argument, in which case it
does nothing.
@item insert-buffer
Insert after point the contents of the user specified buffer.
Puts mark after the inserted text.
@item insert-file
Insert contents of the user specified file into buffer after point.
Set mark after the inserted text.
@item insert-register
Insert contents of the user specified register.
Puts point before and mark after the inserted text.
@item isearch-backward
Do incremental search backward.
With a prefix argument, do a regular expression search instead.
As you type characters, they add to the search string and are found.
Type return to exit, leaving point at location found.
Type @kbd{C-r} to search again backward, @kbd{C-s} to search again forward.
@kbd{C-g} when search is successful aborts and moves point to starting point.
@item isearch-backward-regexp
Do incremental search forward for regular expression.
With a prefix argument, do a regular string search instead.
Like ordinary incremental search except that your input
is treated as a regexp.  See @kbd{C-s} for more info.
@item isearch-forward
Do incremental search forward.
With a prefix argument, do an incremental regular expression search instead.
As you type characters, they add to the search string and are found.
Type return to exit, leaving point at location found.
Type @kbd{C-s} to search again forward, @kbd{C-r} to search again backward.
@kbd{C-g} when search is successful aborts and moves point to starting point.
@item isearch-forward-regexp
Do incremental search forward for regular expression.
With a prefix argument, do a regular string search instead.
Like ordinary incremental search except that your input
is treated as a regexp.  See @kbd{C-s} for more info.
@item just-one-space
Delete all spaces and tabs around point, leaving one space.
@item keyboard-quit
Cancel current command.
@item kill-buffer
Kill the current buffer or the user specified one.
@item kill-line
Kill the rest of the current line; if no non-blanks there, kill thru newline.
@item kill-region
Kill between point and mark.
The text is deleted but saved in the kill ring.
The command @kbd{C-y} (yank) can retrieve it from there.

If the buffer is read-only, Zile will beep and refrain from deleting
the text, but put the text in the kill ring anyway.  This means that
you can use the killing commands to copy text from a read-only buffer.

If the previous command was also a kill command,
the text killed this time appends to the text killed last time
to make one entry in the kill ring.
@item kill-sexp
Kill the sexp (balanced expression) following the cursor.
With ARG, kill that many sexps after the cursor.
Negative arg -N means kill N sexps before the cursor.
@item kill-word
Kill characters forward until encountering the end of a word.
With argument, do this that many times.
@item list-buffers
Display a list of names of existing buffers.
The list is displayed in a buffer named @samp{*Buffer List*}.
Note that buffers with names starting with spaces are omitted.

@c LINT IGNORE
@itemize -
@item The @samp{M} column contains a @samp{*} for buffers that are modified.
@item The @samp{R} column contains a @samp{%} for buffers that are read-only.
@end itemize
@c LINT END IGNORE
@item list-registers
List defined registers.
@item mark-paragraph
Put point at beginning of this paragraph, mark at end.
The paragraph marked is the one that contains point or follows point.
@item mark-sexp
Set mark argument sexps from point.
The place mark goes is the same place @kbd{C-M-f} would
move to with the same argument.
@item mark-whole-buffer
Put point at beginning and mark at end of buffer.
@item mark-word
Set mark argument words away from point.
@item name-last-kbd-macro
Assign a name to the last keyboard macro defined.
Argument SYMBOL is the name to define.
The symbol's function definition becomes the keyboard macro string.
Such a "function" cannot be called from Lisp, but it is a valid editor command.
@item newline
Insert a newline at the current point position into
the current buffer.
@item newline-and-indent
Insert a newline, then indent.
Indentation is done using the @i{indent-for-tab-command} function.
@item next-line
Move cursor vertically down one line.
If there is no character in the target line exactly in the current column,
the cursor is positioned after the character in that line which spans this
column, or at the end of the line if it is not long enough.
@item open-line
Insert a newline and leave point before it.
@item other-window
Select the first different window on the screen.
All windows are arranged in a cyclic order.
This command selects the window one step away in that order.
@item overwrite-mode
In @i{Overwrite Mode}, printing characters typed in replace existing text
on a one-for-one basis, rather than pushing it to the right.  At the
end of a line, such characters extend the line.
@kbd{C-q} still inserts characters in @i{Overwrite Mode}; this
is supposed to make it easier to insert characters when necessary.
@item previous-line
Move cursor vertically up one line.
If there is no character in the target line exactly over the current column,
the cursor is positioned after the character in that line which spans this
column, or at the end of the line if it is not long enough.
@item query-replace
Replace occurrences of a string with other text.
As each match is found, the user must type a character saying
what to do with it.
@item quoted-insert
Read next input character and insert it.
This is useful for inserting control characters.
You may also type up to 3 octal digits, to insert a character with that code.
@item recenter
Center point in window and redisplay screen.
The desired position of point is always relative to the current window.
@item replace-string
Replace occurrences of a string with other text.
@item save-buffer
Save current buffer in visited file if modified.  By default, makes the
previous version into a backup file if this is the first save.
@item save-buffers-kill-zile
Offer to save each buffer, then kill this Zile process.
@item save-some-buffers
Save some modified file-visiting buffers.  Asks user about each one.
@item scroll-down
Scroll text of current window downward near full screen.
@item scroll-up
Scroll text of current window upward near full screen.
@item search-backward
Search backward from point for the user specified text.
@item search-backward-regexp
Search backward from point for match for regular expression REGEXP.
@item search-forward
Search forward from point for the user specified text.
@item search-forward-regexp
Search forward from point for regular expression REGEXP.
@item self-insert-command
Insert the character you type.
@item set-fill-column
Set the fill column.
If an argument value is passed, set the @samp{fill-column} variable with
that value, otherwise with the current column value.
@item set-mark-command
Set mark at where point is.
@item set-variable
Set a variable value to the user specified value.
@item shell-command
Reads a line of text using the minibuffer and creates an inferior shell
to execute the line as a command.

Standard input from the command comes from the null device.  If the
shell command produces any output, the output goes to a Zile buffer
named @samp{*Shell Command Output*}, which is displayed in another window
but not selected.

If the output is one line, it is displayed in the echo area.
A numeric argument, as in @kbd{M-1 M-!} or @kbd{C-u M-!}, directs this
command to insert any output into the current buffer.
@item shell-command-on-region
Reads a line of text using the minibuffer and creates an inferior shell
to execute the line as a command; passes the contents of the region as
input to the shell command.

If the shell command produces any output, the output goes to a Zile buffer
named @samp{*Shell Command Output*}, which is displayed in another window
but not selected.

If the output is one line, it is displayed in the echo area.
A numeric argument, as in @kbd{M-1 M-|} or @kbd{C-u M-|}, directs output
to the current buffer,
then the old region is deleted first and the output replaces it as the
contents of the region.
@item shrink-window
Make current window one line smaller.
@item split-window
Split current window into two windows, one above the other.
Both windows display the same buffer now current.
@item start-kbd-macro
Record subsequent keyboard input, defining a keyboard macro.
The commands are recorded even as they are executed.
Use @kbd{C-x )} to finish recording and make the macro available.
@item suspend-zile
Stop Zile and return to superior process.
@item switch-to-buffer
Select to the user specified buffer in the current window.
@item tab-to-tab-stop
Insert a tabulation at the current point position into
the current buffer.
@item tabify
Convert multiple spaces in region to tabs when possible.
A group of spaces is partially replaced by tabs
when this can be done without changing the column they end at.
The variable @samp{tab-width} controls the spacing of tab stops.
@item toggle-read-only
Change whether this buffer is visiting its file read-only.
@item transient-mark-mode
Toggle Transient Mark mode.
With arg, turn Transient Mark mode on if arg is positive, off otherwise.
@item transpose-chars
Interchange characters around point, moving forward one character.
If at end of line, the previous two chars are exchanged.
@item transpose-lines
Exchange current line and previous line, leaving point after both.
With argument ARG, takes previous line and moves it past ARG lines.
With argument 0, interchanges line point is in with line mark is in.
@item transpose-sexps
Like @kbd{M-t} but applies to sexps.
@item transpose-words
Interchange words around point, leaving point at end of them.
@item undo
Undo some previous changes.
Repeat this command to undo more changes.
@item universal-argument
Begin a numeric argument for the following command.
Digits or minus sign following @kbd{C-u} make up the numeric argument.
@kbd{C-u} following the digits or minus sign ends the argument.
@kbd{C-u} without digits or minus sign provides 4 as argument.
Repeating @kbd{C-u} without digits or minus sign multiplies the argument
by 4 each time.
@item untabify
Convert all tabs in region to multiple spaces, preserving columns.
The variable @samp{tab-width} controls the spacing of tab stops.
@item upcase-region
Convert the region to upper case.
@item upcase-word
Convert following word (or argument N words) to upper case, moving over.
@item view-zile-FAQ
Show the Zile @i{Frequently Asked Questions} list (FAQ).
@item where-is
Show the key or keys to which the given command is bound.
@item write-file
Write current buffer into the user specified file.
Makes buffer visit that file, and marks it not modified.
@item yank
Reinsert the last stretch of killed text.
More precisely, reinsert the stretch of killed text most recently
killed @i{or} yanked.  Put point at end, and set mark at beginning.
@item zile-version
Show the version of Zile.
@end table
@c LINT END FUNC

@c ---------------------------------------------------------------------------
@node Variables, Help and bug reports, Functions, Top
@chapter Variables

This table contains the full list of available variables, that can be
modified at run-time with the @samp{set-variable} function or set at start-up
in the @file{.zile} initialization file.

@c LINT VAR
@table @code
@item auto-fill-mode
If non-nil, @i{Auto Fill Mode} is automatically enabled.  Default
value is @samp{nil}.
@item backup-directory
The directory for backup files, which must exist.  If this variable is
@samp{nil}, the backup is made in the original file's directory.
Default value is @samp{nil}.
@item case-fold-search
Non-nil means searches ignore case.
@item case-replace
Non-nil means `query-replace' should preserve case in replacements.
@item fill-column
Column beyond which automatic line-wrapping should happen.
Automatically becomes buffer-local when set in any fashion.
Default value is @samp{72}.
@item highlight-nonselected-windows
If non-nil, highlight region even in nonselected windows.  Default
value is @samp{nil}.
@item indent-tabs-mode
If non-nil, insert-tab inserts `real' tabs; otherwise, it always inserts spaces.
Default value is @samp{nil}.
@item inhibit-splash-screen
Non-nil inhibits the startup screen.
It also inhibits display of the initial message in the `*scratch*' buffer.
Default value is @samp{nil}.
@item kill-whole-line
If non-nil, `kill-line' with no arg at the beginning of a line kills the whole line.
Default value is @samp{nil}.
@item make-backup-files
Non-nil means make a backup of a file the first time it is saved.
This is done by appending `@samp{~}' to the file name.
Default value is @samp{t}.
@item ring-bell
Non-nil means ring the terminal bell on any error.
Default value is @samp{t}.
@item standard-indent
Default number of columns for margin-changing functions to indent.
Default values is @samp{4}.
@item tab-always-indent
Controls the operation of the @kbd{TAB} key.
If @samp{t}, hitting @kbd{TAB} always just indents the current line.
If @samp{nil}, hitting @kbd{TAB} indents the current line if point is at the
left margin or in the line's indentation, otherwise it inserts a
"real" TAB character.
Default value is @samp{t}.
@item tab-width
Distance between tab stops (for display of tab characters), in columns.
Automatically becomes buffer-local when set in any fashion.
Default value is @samp{8}.
@item transient-mark-mode
If non-nil, deactivates the mark when the buffer contents change.
Also enables highlighting of the region whenever the mark is active.
The variable `highlight-nonselected-windows' controls whether to
highlight all windows or just the selected window.
Default value is @samp{t}.
@end table
@c LINT END VAR

@c ---------------------------------------------------------------------------
@node Help and bug reports, GNU Free Documentation License, Variables, Top
@chapter Help and bug reports

Questions, comments and requests should be sent to
@email{help-zile@@gnu.org}. Bug reports should be sent to
@email{bug-zile@@gnu.org}. Savannah users are welcome to file bug reports,
feature requests and patches directly in the relevant tracker at
@uref{http://savannah.gnu.org/projects/zile/}.

@c ---------------------------------------------------------------------------
@node GNU Free Documentation License,  , Help and bug reports, Top
@chapter The GNU Free Documentation License

@center Version 1.2, November 2002

@display
Copyright @copyright{} 2000,2001,2002 Free Software Foundation, Inc.
51 Franklin St, Fifth Floor, Boston, MA  02110-1301, 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
functional and useful 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, in any medium, that
contains a notice placed by the copyright holder saying it can be
distributed under the terms of this License.  Such a notice grants a
world-wide, royalty-free license, unlimited in duration, to use that
work under the conditions stated herein.  The ``Document'', below,
refers to any such manual or work.  Any member of the public is a
licensee, and is addressed as ``you''.  You accept the license if you
copy, modify or distribute the work in a way requiring permission
under copyright law.

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.  (Thus, 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.  If a
section does not fit the above definition of Secondary then it is not
allowed to be designated as Invariant.  The Document may contain zero
Invariant Sections.  If the Document does not identify any Invariant
Sections then there are none.

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 Front-Cover Text may
be at most 5 words, and a Back-Cover Text may be at most 25 words.

A ``Transparent'' copy of the Document means a machine-readable copy,
represented in a format whose specification is available to the
general public, that is suitable for revising the document
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, or absence of markup, has been arranged to thwart
or discourage subsequent modification by readers is not Transparent.
An image format is not Transparent if used for any substantial amount
of text.  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},
PostScript or @acronym{PDF} designed for human modification.  Examples
of transparent image formats include @acronym{PNG}, @acronym{XCF} and
@acronym{JPG}.  Opaque formats include 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},
PostScript or @acronym{PDF} 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.

A section ``Entitled XYZ'' means a named subunit of the Document whose
title either is precisely XYZ or contains XYZ in parentheses following
text that translates XYZ in another language.  (Here XYZ stands for a
specific section name mentioned below, such as ``Acknowledgements'',
``Dedications'', ``Endorsements'', or ``History''.)  To ``Preserve the Title''
of such a section when you modify the Document means that it remains a
section ``Entitled XYZ'' according to this definition.

The Document may include Warranty Disclaimers next to the notice which
states that this License applies to the Document.  These Warranty
Disclaimers are considered to be included by reference in this
License, but only as regards disclaiming warranties: any other
implication that these Warranty Disclaimers may have is void and has
no effect on the meaning of this License.

@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 (or copies in media that commonly have
printed covers) 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 computer-network location from which the general network-using
public has access to download using public-standard network protocols
a complete Transparent copy of the Document, free of added material.
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 fewer than five),
unless they release you from this requirement.

@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'', Preserve 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
For any section Entitled ``Acknowledgements'' or ``Dedications'', Preserve
the Title of the section, and preserve in the section all the
substance and tone of each of the contributor acknowledgements 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 to be Entitled ``Endorsements'' or
to conflict in title with any Invariant Section.

@item
Preserve any Warranty Disclaimers.
@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, and that you preserve all their Warranty Disclaimers.

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 ``Acknowledgements'',
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, is called an ``aggregate'' if the copyright
resulting from the compilation is not used to limit the legal rights
of the compilation's users beyond what the individual works permit.
When the Document is included in an aggregate, this License does not
apply to the other works in the aggregate which 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 half of
the entire aggregate, the Document's Cover Texts may be placed on
covers that bracket the Document within the aggregate, or the
electronic equivalent of covers if the Document is in electronic form.
Otherwise they must appear on printed covers that bracket 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, and all the license notices in the
Document, and any Warranty Disclaimers, provided that you also include
the original English version of this License and the original versions
of those notices and disclaimers.  In case of a disagreement between
the translation and the original version of this License or a notice
or disclaimer, the original version will prevail.

If a section in the Document is Entitled ``Acknowledgements'',
``Dedications'', or ``History'', the requirement (section 4) to Preserve
its Title (section 1) will typically require changing the actual
title.

@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

@contents

@bye

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