Re-generated libconfig parser and scanner

This overrides previous manual edits to the machine-generated files, and
is supposed to make it much easier to maintain in future.

There should be no functional changes at all, but if there's any issue,
please let me know.

Signed-off-by: Haru <haru@dotalux.com>

4 files changed, 2536 insertions, 0 deletions

diff --git a/3rdparty/libconfig/extra/doc/LGPL.texi b/3rdparty/libconfig/extra/doc/LGPL.texi
new file mode 100644
index 000000000..e371ac0d0
--- /dev/null
+++ b/3rdparty/libconfig/extra/doc/LGPL.texi
@@ -0,0 +1,590 @@
+@c \input texinfo.tex    @c -*-texinfo-*-
+@c 
+@c %**start of header
+
+@c All text is ignored before the setfilename.
+@setfilename LGPL.info
+
+@center GNU LESSER GENERAL PUBLIC LICENSE
+@center Version 2.1, February 1999
+
+@sp 1
+
+Copyright @copyright{} 1991, 1999 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.
+
+[This is the first released version of the Lesser GPL.  It also counts
+as the successor of the GNU Library Public License, version 2, hence the
+version number 2.1.]
+
+@sp 1
+@center Preamble
+@sp 1
+
+The licenses for most software are designed to take away your freedom to
+share and change it.  By contrast, the GNU General Public Licenses are
+intended to guarantee your freedom to share and change free software--to
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+it too, but we suggest you first think carefully about whether this
+license or the ordinary General Public License is the better strategy to
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+@item
+The Free Software Foundation may publish revised and/or new versions of
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+
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+@center NO WARRANTY
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+
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+BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR
+THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
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+@item
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+
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+
+@sp 1
+@center END OF TERMS AND CONDITIONS
+@sp 1
+@page
+@center How to Apply These Terms to Your New Libraries
+
+If you develop a new library, and you want it to be of the greatest
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+@t{
+<one line to give the library's name and a brief idea of what it does.>
+Copyright (C) <year>  <name of author>
+
+This library is free software; you can redistribute it and/or
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+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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+
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+}
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+
+Also add information on how to contact you by electronic and paper mail.
+
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+school, if any, to sign a ``copyright disclaimer'' for the library, if
+necessary.  Here is a sample; alter the names:
+
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+@t{
+Yoyodyne, Inc., hereby disclaims all copyright interest in the
+library `Frob' (a library for tweaking knobs) written by James Random Hacker.
+
+<signature of Ty Coon>, 1 April 1990
+Ty Coon, President of Vice
+}
+@end format
+
+That's all there is to it!
+
+@c @bye
diff --git a/3rdparty/libconfig/extra/doc/Makefile b/3rdparty/libconfig/extra/doc/Makefile
new file mode 100644
index 000000000..fd84597a6
--- /dev/null
+++ b/3rdparty/libconfig/extra/doc/Makefile
@@ -0,0 +1,18 @@
+HTMLS = libconfig.html
+TEXINFOS = libconfig.texi
+MAKEINFOHTML = $(MAKEINFO) --html
+MAKEINFO = makeinfo
+
+all: html
+
+.SUFFIXES: .html .texi
+
+libconfig.html: $(TEXINFOS)
+
+clean:
+	@-test -z "$(HTMLS)" || rm -rf libconfig.html
+
+.PHONY: all clean html
+
+html: $(HTMLS)
+	$(MAKEINFOHTML) --no-split $(TEXINFOS)
diff --git a/3rdparty/libconfig/extra/doc/Makefile.in b/3rdparty/libconfig/extra/doc/Makefile.in
new file mode 100644
index 000000000..fd84597a6
--- /dev/null
+++ b/3rdparty/libconfig/extra/doc/Makefile.in
@@ -0,0 +1,18 @@
+HTMLS = libconfig.html
+TEXINFOS = libconfig.texi
+MAKEINFOHTML = $(MAKEINFO) --html
+MAKEINFO = makeinfo
+
+all: html
+
+.SUFFIXES: .html .texi
+
+libconfig.html: $(TEXINFOS)
+
+clean:
+	@-test -z "$(HTMLS)" || rm -rf libconfig.html
+
+.PHONY: all clean html
+
+html: $(HTMLS)
+	$(MAKEINFOHTML) --no-split $(TEXINFOS)
diff --git a/3rdparty/libconfig/extra/doc/libconfig.texi b/3rdparty/libconfig/extra/doc/libconfig.texi
new file mode 100644
index 000000000..52dca20fc
--- /dev/null
+++ b/3rdparty/libconfig/extra/doc/libconfig.texi
@@ -0,0 +1,1910 @@
+\input texinfo.tex    @c -*-texinfo-*-
+@c
+@c %**start of header
+
+@c All text is ignored before the setfilename.
+@setfilename libconfig.info
+@settitle libconfig
+
+@set edition 1.4.9
+@set update-date 28 September 2012
+@set subtitle-text A Library For Processing Structured Configuration Files
+@set author-text Mark A.@: Lindner
+
+@comment %**end of header
+
+@dircategory Software libraries
+@direntry
+* libconfig: (libconfig).       A Library For Processing Structured Configuration Files
+@end direntry
+
+
+@tex
+\global\emergencystretch = .3\hsize
+@end tex
+
+@setchapternewpage odd
+
+@titlepage
+
+@title libconfig
+@subtitle @value{subtitle-text}
+@subtitle Version @value{edition}
+@subtitle @value{update-date}
+
+@author @value{author-text}
+
+@page
+@vskip 0pt plus 1filll
+Copyright @copyright{} 2005-2012  Mark A Lindner
+
+Permission is granted to make and distribute verbatim copies of
+this manual provided the copyright notice and this permission notice
+are preserved on all copies.
+
+Permission is granted to copy and distribute modified versions of this
+manual under the conditions for verbatim copying, provided that the entire
+resulting derived work is distributed under the terms of a permission
+notice identical to this one.
+
+@end titlepage
+
+@c Give the HTML output a title page that somewhat resembles the printed one
+@ifhtml
+@html
+<hr noshade size=6 color="black">
+<div align=right>@value{subtitle-text}<br>
+Version @value{edition}<br>
+@value{update-date}</div>
+<br><br><br><br>
+<font size=+1>@value{author-text}</font>
+<hr size=3 noshade color="black">
+<br><br>
+@end html
+@end ifhtml
+
+@contents
+
+@ifnottex
+@node Top
+@comment  node-name,  next,  previous,  up
+@top libconfig
+@end ifnottex
+
+@menu
+* Introduction::
+* Configuration Files::
+* The C API::
+* The C++ API::
+* Example Programs::
+* Configuration File Grammar::
+* License::
+* Function Index::
+* Type Index::
+* Concept Index::
+@end menu
+
+@node Introduction, Configuration Files, Top, Top
+@comment  node-name,  next,  previous,  up
+@menu
+* Why Another Configuration File Library?::
+* Using the Library from a C Program::
+* Using the Library from a C++ Program::
+* Multithreading Issues::
+* Internationalization Issues::
+* Compiling Using pkg-config::
+* Version Test Macros::
+@end menu
+@chapter Introduction
+
+@i{Libconfig} is a library for reading, manipulating, and writing
+structured configuration files. The library features a fully
+reentrant parser and includes bindings for both the C and C++
+programming languages.
+
+The library runs on modern POSIX-compilant systems, such as Linux,
+Solaris, and Mac OS X (Darwin), as well as on Microsoft Windows
+2000/XP and later (with either Microsoft Visual Studio 2005 or later,
+or the GNU toolchain via the MinGW environment).
+
+@node Why Another Configuration File Library?, Using the Library from a C Program, , Introduction
+@comment  node-name,  next,  previous,  up
+@section Why Another Configuration File Library?
+
+There are several open-source configuration file libraries available
+as of this writing. This library was written because each of those
+libraries falls short in one or more ways. The main features of
+@i{libconfig} that set it apart from the other libraries are:
+
+@itemize @bullet
+
+@item A fully reentrant parser. Independent configurations can be parsed in concurrent threads at the same time.
+
+@item Both C @i{and} C++ bindings, as well as hooks to allow for the creation of wrappers in other languages.
+
+@item A simple, structured configuration file format that is more
+readable and compact than XML and more flexible than the obsolete but
+prevalent Windows ``INI'' file format.
+
+@item A low-footprint implementation (just 37K for the C library and 76K for
+the C++ library) that is suitable for memory-constrained systems.
+
+@item Proper documentation.
+
+@end itemize
+
+@node Using the Library from a C Program, Using the Library from a C++ Program, Why Another Configuration File Library?, Introduction
+@comment  node-name,  next,  previous,  up
+@section Using the Library from a C Program
+
+To use the library from C code, include the following preprocessor
+directive in your source files:
+
+@sp 1
+@smallexample
+#include <libconfig.h>
+@end smallexample
+@sp 1
+
+To link with the library, specify @samp{-lconfig} as an argument to the
+linker.
+
+@node Using the Library from a C++ Program, Multithreading Issues, Using the Library from a C Program, Introduction
+@comment  node-name,  next,  previous,  up
+@section Using the Library from a C++ Program
+
+To use the library from C++, include the following preprocessor
+directive in your source files:
+
+@sp 1
+@smallexample
+#include <libconfig.h++>
+@end smallexample
+@sp 1
+
+Or, alternatively:
+
+@sp 1
+@smallexample
+#include <libconfig.hh>
+@end smallexample
+@sp 1
+@page
+The C++ API classes are defined in the namespace @samp{libconfig}, hence the
+following statement may optionally be used:
+
+@sp 1
+@smallexample
+using namespace libconfig;
+@end smallexample
+@sp 1
+
+To link with the library, specify @samp{-lconfig++} as an argument to
+the linker.
+
+@node Multithreading Issues, Internationalization Issues, Using the Library from a C++ Program, Introduction
+@comment  node-name,  next,  previous,  up
+@section Multithreading Issues
+
+@i{Libconfig} is fully @dfn{reentrant}; the functions in the library
+do not make use of global variables and do not maintain state between
+successive calls. Therefore two independent configurations may be safely
+manipulated concurrently by two distinct threads.
+
+@i{Libconfig} is not @dfn{thread-safe}. The library is not aware of
+the presence of threads and knows nothing about the host system's
+threading model. Therefore, if an instance of a configuration is to be
+accessed from multiple threads, it must be suitably protected by
+synchronization mechanisms like read-write locks or mutexes; the
+standard rules for safe multithreaded access to shared data must be
+observed.
+
+@i{Libconfig} is not @dfn{async-safe}. Calls should not be made into
+the library from signal handlers, because some of the C library
+routines that it uses may not be async-safe.
+
+@i{Libconfig} is not guaranteed to be @dfn{cancel-safe}. Since it is
+not aware of the host system's threading model, the library does not
+contain any thread cancellation points. In most cases this will not be
+an issue for multithreaded programs. However, be aware that some of
+the routines in the library (namely those that read/write
+configurations from/to files or streams) perform I/O using C library
+routines which may potentially block; whether or not these C library
+routines are cancel-safe depends on the host system.
+
+@node Internationalization Issues, Compiling Using pkg-config, Multithreading Issues, Introduction
+@comment  node-name,  next,  previous,  up
+@section Internationalization Issues
+
+@cindex Unicode
+@cindex UTF-8
+@i{Libconfig} does not natively support Unicode configuration files,
+but string values may contain Unicode text encoded in UTF-8; such
+strings will be treated as ordinary 8-bit ASCII text by the
+library. It is the responsibility of the calling program to perform
+the necessary conversions to/from wide (@t{wchar_t}) strings using the
+wide string conversion functions such as @t{mbsrtowcs()} and
+@t{wcsrtombs()} or the @t{iconv()} function of the @i{libiconv}
+library.
+
+@cindex locale
+The textual representation of a floating point value varies by
+locale. However, the @i{libconfig} grammar specifies that
+floating point values are represented using a period (`.') as the
+radix symbol; this is consistent with the grammar of most programming
+languages. When a configuration is read in or written out,
+@i{libconfig} temporarily changes the @t{LC_NUMERIC} category of the
+locale of the calling thread to the ``C'' locale to ensure consistent
+handling of floating point values regardless of the locale(s) in use
+by the calling program.
+
+Note that the MinGW environment does not (as of this writing) provide
+functions for changing the locale of the calling thread. Therefore,
+when using @i{libconfig} in that environment, the calling program is
+responsible for changing the @t{LC_NUMERIC} category of the locale to
+the "C" locale before reading or writing a configuration.
+
+@node Compiling Using pkg-config, Version Test Macros, Internationalization Issues, Introduction
+@comment  node-name,  next,  previous,  up
+@section Compiling Using pkg-config
+
+On UNIX systems you can use the @i{pkg-config} utility (version 0.20
+or later) to automatically select the appropriate compiler and linker
+switches for @i{libconfig}. Ensure that the environment variable
+@code{PKG_CONFIG_PATH} contains the absolute path to the
+@file{lib/pkgconfig} subdirectory of the @i{libconfig} installation. Then,
+you can compile and link C programs with @i{libconfig} as follows:
+
+@smallexample
+gcc `pkg-config --cflags libconfig` myprogram.c -o myprogram \
+    `pkg-config --libs libconfig`
+@end smallexample
+@sp 1
+
+And similarly, for C++ programs:
+
+@smallexample
+g++ `pkg-config --cflags libconfig++` myprogram.cpp -o myprogram \
+    `pkg-config --libs libconfig++`
+@end smallexample
+
+@sp 1
+Note the backticks in the above examples.
+
+When using @b{autoconf}, the @code{PKG_CHECK_MODULES} m4 macro may be used to check for the presence of a given version of @i{libconfig}, and set the appropriate Makefile variables automatically. For example:
+
+@smallexample
+PKG_CHECK_MODULES([LIBCONFIGXX], [libconfig++ >= 1.4],,
+  AC_MSG_ERROR([libconfig++ 1.4 or newer not found.])
+)
+@end smallexample
+
+In the above example, if @i{libconfig++} version 1.4 or newer is found,
+the Makefile variables @code{LIBCONFIGXX_LIBS} and @code{LIBCONFIGXX_CFLAGS} will be
+set to the appropriate compiler and linker flags for compiling with
+@i{libconfig}, and if it is not found, the configure script will abort
+with an error to that effect.
+
+@node Version Test Macros, , Compiling Using pkg-config, Introduction
+@comment  node-name,  next,  previous,  up
+@section Version Test Macros
+
+The @file{libconfig.h} header declares the following macros:
+
+@defmac LIBCONFIG_VER_MAJOR
+@defmacx LIBCONFIG_VER_MINOR
+@defmacx LIBCONFIG_VER_REVISION
+
+These macros represent the major version, minor version, and revision
+of the @i{libconfig} library. For example, in @i{libconfig} 1.4 these
+are defined as @samp{1}, @samp{4}, and @samp{0}, respectively. These
+macros can be used in preprocessor directives to determine which
+@i{libconfig} features and/or APIs are present. For example:
+
+@smallexample
+#if (((LIBCONFIG_VER_MAJOR == 1) && (LIBCONFIG_VER_MINOR >= 4)) \
+     || (LIBCONFIG_VER_MAJOR > 1))
+  /* use features present in libconfig 1.4 and later */
+#endif
+@end smallexample
+
+These macros were introduced in @i{libconfig} 1.4.
+
+@end defmac
+
+Similarly, the @file{libconfig.h++} header declares the following macros:
+
+@defmac LIBCONFIGXX_VER_MAJOR
+@defmacx LIBCONFIGXX_VER_MINOR
+@defmacx LIBCONFIGXX_VER_REVISION
+
+These macros represent the major version, minor version, and revision
+of the @i{libconfig++} library.
+
+@end defmac
+
+@node Configuration Files, The C API, Introduction, Top
+@comment  node-name,  next,  previous,  up
+@menu
+* Settings::
+* Groups::
+* Arrays::
+* Lists::
+* Integer Values::
+* 64-bit Integer Values::
+* Floating Point Values::
+* Boolean Values::
+* String Values::
+* Comments::
+* Include Directives::
+@end menu
+@chapter Configuration Files
+
+@i{Libconfig} supports structured, hierarchical configurations. These
+configurations can be read from and written to files and manipulated
+in memory.
+
+@cindex setting
+@cindex value
+@cindex scalar value
+@cindex array
+@cindex group
+@cindex list
+@cindex configuration
+A @dfn{configuration} consists of a group of @dfn{settings}, which
+associate names with values. A @dfn{value} can be one of the
+following:
+
+@itemize @bullet
+@item A @dfn{scalar value}: integer, 64-bit integer, floating-point number, boolean,
+or string
+@item An @dfn{array}, which is a sequence of scalar values, all of which must have the same type
+@item A @dfn{group}, which is a collection of settings
+@item A @dfn{list}, which is a sequence of values of any type, including other lists
+@end itemize
+
+Consider the following configuration file for a hypothetical GUI
+application, which illustrates all of the elements of the configuration
+file grammar.
+
+@sp 1
+@cartouche
+@smallexample
+# Example application configuration file
+
+version = "1.0";
+
+application:
+@{
+  window:
+  @{
+    title = "My Application";
+    size = @{ w = 640; h = 480; @};
+    pos = @{ x = 350; y = 250; @};
+  @};
+
+  list = ( ( "abc", 123, true ), 1.234, ( /* an empty list */) );
+
+  books = ( @{ title  = "Treasure Island";
+              author = "Robert Louis Stevenson";
+              price  = 29.95;
+              qty    = 5; @},
+            @{ title  = "Snow Crash";
+              author = "Neal Stephenson";
+              price  = 9.99;
+              qty    = 8; @} );
+
+  misc:
+  @{
+    pi = 3.141592654;
+    bigint = 9223372036854775807L;
+    columns = [ "Last Name", "First Name", "MI" ];
+    bitmask = 0x1FC3;
+  @};
+@};
+@end smallexample
+@end cartouche
+@sp 1
+
+@cindex path
+Settings can be uniquely identified within the configuration by a
+@dfn{path}. The path is a dot-separated sequence of names, beginning
+at a top-level group and ending at the setting itself. Each name in
+the path is the name of a setting; if the setting has no name because
+it is an element in a list or array, an integer index in square
+brackets can be used as the name.
+
+For example, in our hypothetical configuration file, the path to the
+@code{x} setting is @code{application.window.pos.x}; the path to the
+@code{version} setting is simply @code{version}; and the path to the
+@code{title} setting of the second book in the @code{books} list is
+@code{application.books.[1].title}.
+
+The datatype of a value is determined from the format of the value
+itself. If the value is enclosed in double quotes, it is treated as a
+string. If it looks like an integer or floating point number, it is
+treated as such. If it is one of the values @code{TRUE}, @code{true},
+@code{FALSE}, or @code{false} (or any other mixed-case version of
+those tokens, e.g., @code{True} or @code{FaLsE}), it is treated as a
+boolean. If it consists of a comma-separated list of values enclosed
+in square brackets, it is treated as an array. And if it consists of a
+comma-separated list of values enclosed in parentheses, it is treated
+as a list. Any value which does not meet any of these criteria is
+considered invalid and results in a parse error.
+
+All names are case-sensitive. They may consist only of alphanumeric
+characters, dashes (@samp{-}), underscores (@samp{_}), and asterisks
+(@samp{*}), and must begin with a letter or asterisk. No other
+characters are allowed.
+
+In C and C++, integer, 64-bit integer, floating point, and string
+values are mapped to the types @code{int}, @code{long long},
+@code{double}, and @code{const char *}, respectively. The boolean type
+is mapped to @code{int} in C and @code{bool} in C++.
+
+The following sections describe the elements of the configuration file
+grammar in additional detail.
+
+@node Settings, Groups, , Configuration Files
+@comment  node-name,  next,  previous,  up
+@section Settings
+
+A setting has the form:
+
+@i{name} @b{=} @i{value} @b{;}
+
+or:
+
+@i{name} @b{:} @i{value} @b{;}
+
+The trailing semicolon is optional. Whitespace is not significant.
+
+The value may be a scalar value, an array, a group, or a list.
+
+@node Groups, Arrays, Settings, Configuration Files
+@comment  node-name,  next,  previous,  up
+@section Groups
+
+A group has the form:
+
+@b{@{}
+   @i{settings ...}
+@b{@}}
+
+Groups can contain any number of settings, but each setting must have
+a unique name within the group.
+
+@node Arrays, Lists, Groups, Configuration Files
+@comment  node-name,  next,  previous,  up
+@section Arrays
+
+An array has the form:
+
+@b{[} @i{value}@b{,} @i{value ...} @b{]}
+
+An array may have zero or more elements, but the elements must all be
+scalar values of the same type.
+
+@node Lists, Integer Values, Arrays, Configuration Files
+@comment  node-name,  next,  previous,  up
+@section Lists
+
+A list has the form:
+
+@b{(} @i{value}@b{,} @i{value ...} @b{)}
+
+A list may have zero or more elements, each of which can be a scalar
+value, an array, a group, or another list.
+
+@node Integer Values, 64-bit Integer Values, Lists, Configuration Files
+@comment  node-name,  next,  previous,  up
+@section Integer Values
+
+Integers can be represented in one of two ways: as a series of one or
+more decimal digits (@samp{0} - @samp{9}), with an optional leading
+sign character (@samp{+} or @samp{-}); or as a hexadecimal value
+consisting of the characters @samp{0x} followed by a series of one or
+more hexadecimal digits (@samp{0} - @samp{9}, @samp{A} - @samp{F},
+@samp{a} - @samp{f}).
+
+@node 64-bit Integer Values, Floating Point Values, Integer Values, Configuration Files
+@comment  node-name,  next,  previous,  up
+@section 64-bit Integer Values
+
+Long long (64-bit) integers are represented identically to integers,
+except that an 'L' character is appended to indicate a 64-bit
+value. For example, @samp{0L} indicates a 64-bit integer value 0.
+
+@node Floating Point Values, Boolean Values, 64-bit Integer Values, Configuration Files
+@comment  node-name,  next,  previous,  up
+@section Floating Point Values
+
+Floating point values consist of a series of one or more digits, one
+decimal point, an optional leading sign character (@samp{+} or
+@samp{-}), and an optional exponent. An exponent consists of the
+letter @samp{E} or @samp{e}, an optional sign character, and a series
+of one or more digits.
+
+@node Boolean Values, String Values, Floating Point Values, Configuration Files
+@comment  node-name,  next,  previous,  up
+@section Boolean Values
+
+Boolean values may have one of the following values: @samp{true},
+@samp{false}, or any mixed-case variation thereof.
+
+@node String Values, Comments, Boolean Values, Configuration Files
+@comment  node-name,  next,  previous,  up
+@section String Values
+
+@cindex escape sequence
+String values consist of arbitrary text delimited by double
+quotes. Literal double quotes can be escaped by preceding them with a
+backslash: @samp{\"}. The escape sequences @samp{\\}, @samp{\f},
+@samp{\n}, @samp{\r}, and @samp{\t} are also recognized, and have the
+usual meaning.
+
+In addition, the @samp{\x} escape sequence is supported; this sequence
+must be followed by @i{exactly two} hexadecimal digits, which represent an
+8-bit ASCII value. For example, @samp{\xFF} represents the character
+with ASCII code 0xFF.
+
+No other escape sequences are currently supported.
+
+Adjacent strings are automatically concatenated, as in C/C++ source
+code. This is useful for formatting very long strings as sequences of
+shorter strings. For example, the following constructs are equivalent:
+
+@itemize @bullet
+@item
+@code{"The quick brown fox jumped over the lazy dog."}
+
+@item
+@code{"The quick brown fox"} @*
+@code{" jumped over the lazy dog."}
+
+@item
+@code{"The quick" /* comment */ " brown fox " // another comment} @*
+@code{"jumped over the lazy dog."}
+
+@end itemize
+@page
+@node Comments, Include Directives, String Values, Configuration Files
+@comment  node-name,  next,  previous,  up
+@section Comments
+
+@cindex comment
+Three types of comments are allowed within a configuration:
+
+@itemize @bullet
+
+@item Script-style comments. All text beginning with a @samp{#} character
+to the end of the line is ignored.
+
+@item C-style comments. All text, including line breaks, between a starting
+@samp{/*} sequence and an ending @samp{*/} sequence is ignored.
+
+@item C++-style comments. All text beginning with a @samp{//} sequence to the
+end of the line is ignored.
+
+@end itemize
+
+As expected, comment delimiters appearing within quoted strings are
+treated as literal text.
+
+Comments are ignored when the configuration is read in, so they are
+not treated as part of the configuration. Therefore if the
+configuration is written back out to a stream, any comments that were
+present in the original configuration will be lost.
+
+@node Include Directives, , Comments, Configuration Files
+@comment  node-name,  next,  previous,  up
+@section Include Directives
+
+@cindex include directive
+A configuration file may ``include'' the contents of another file
+using an @i{include directive}. This directive has the effect of
+inlining the contents of the named file at the point of inclusion.
+
+An include directive must appear on its own line in the input. It has
+the form:
+
+@b{@@include "}@i{filename}@b{"}
+
+Any backslashes or double quotes in the filename must be escaped as
+@samp{\\} and @samp{\"}, respectively.
+
+For example, consider the following two configuration files:
+
+@cartouche
+@smallexample
+# file: quote.cfg
+quote = "Criticism may not be agreeable, but it is necessary."
+        " It fulfils the same function as pain in the human"
+        " body. It calls attention to an unhealthy state of"
+        " things.\n"
+        "\t--Winston Churchill";
+@end smallexample
+@end cartouche
+
+@cartouche
+@smallexample
+# file: test.cfg
+info: @{
+  name = "Winston Churchill";
+  @@include "quote.cfg"
+  country = "UK";
+@};
+@end smallexample
+@end cartouche
+
+Include files may be nested to a maximum of 10 levels; exceeding this
+limit results in a parse error.
+
+Like comments, include directives are not part of the configuration
+file syntax. They are processed before the configuration itself is
+parsed. Therefore, they are not preserved when the configuration is
+written back out to a stream. There is presently no support for
+programmatically inserting include directives into a configuration.
+
+@node The C API, The C++ API, Configuration Files, Top
+@comment  node-name,  next,  previous,  up
+@chapter The C API
+
+@tindex config_t
+@tindex config_setting_t
+This chapter describes the C library API. The type @i{config_t}
+represents a configuration, and the type @i{config_setting_t} represents
+a configuration setting.
+
+The boolean values @code{CONFIG_TRUE} and @code{CONFIG_FALSE} are
+macros defined as @code{(1)} and @code{(0)}, respectively.
+
+@deftypefun void config_init (@w{config_t * @var{config}})
+@deftypefunx void config_destroy (@w{config_t * @var{config}})
+
+These functions initialize and destroy the configuration object @var{config}.
+
+@code{config_init()} initializes the @i{config_t} structure pointed to by
+@var{config} as a new, empty configuration.
+
+@code{config_destroy()} destroys the configuration @var{config},
+deallocating all memory associated with the configuration, but does not
+attempt to deallocate the @i{config_t} structure itself.
+
+@end deftypefun
+
+@deftypefun int config_read (@w{config_t * @var{config}}, @w{FILE * @var{stream}})
+
+This function reads and parses a configuration from the given
+@var{stream} into the configuration object @var{config}. It returns
+@code{CONFIG_TRUE} on success, or @code{CONFIG_FALSE} on failure; the
+@code{config_error_text()}, @code{config_error_file()},
+@code{config_error_line()}, and @code{config_error_type()} functions,
+described below, can be used to obtain information about the error.
+
+@end deftypefun
+
+@deftypefun int config_read_file (@w{config_t * @var{config}}, @w{const char * @var{filename}})
+
+This function reads and parses a configuration from the file named
+@var{filename} into the configuration object @var{config}. It returns
+@code{CONFIG_TRUE} on success, or @code{CONFIG_FALSE} on failure; the
+@code{config_error_text()} and @code{config_error_line()} functions,
+described below, can be used to obtain information about the error.
+
+@end deftypefun
+
+@deftypefun int config_read_string (@w{config_t * @var{config}}, @w{const char * @var{str}})
+
+This function reads and parses a configuration from the string
+@var{str} into the configuration object @var{config}. It returns
+@code{CONFIG_TRUE} on success, or @code{CONFIG_FALSE} on failure; the
+@code{config_error_text()} and @code{config_error_line()} functions,
+described below, can be used to obtain information about the error.
+
+@end deftypefun
+
+@deftypefun void config_write (@w{const config_t * @var{config}}, @w{FILE * @var{stream}})
+
+This function writes the configuration @var{config} to the given
+@var{stream}.
+
+@end deftypefun
+
+@deftypefun int config_write_file (@w{config_t * @var{config}}, @w{const char * @var{filename}})
+
+This function writes the configuration @var{config} to the file named
+@var{filename}. It returns @code{CONFIG_TRUE} on success, or
+@code{CONFIG_FALSE} on failure.
+
+@end deftypefun
+
+@deftypefun {const char *} config_error_text (@w{const config_t * @var{config}})
+@deftypefunx {const char *} config_error_file (@w{const config_t * @var{config}})
+@deftypefunx int config_error_line (@w{const config_t * @var{config}})
+
+These functions, which are implemented as macros, return the text,
+filename, and line number of the parse error, if one occurred during a
+call to @code{config_read()}, @code{config_read_string()}, or
+@code{config_read_file()}. Storage for the strings returned by
+@code{config_error_text()} and @code{config_error_file()} are managed
+by the library and released automatically when the configuration is
+destroyed; these strings must not be freed by the caller. If the error
+occurred in text that was read from a string or stream,
+@code{config_error_file()} will return NULL.
+
+@end deftypefun
+
+@deftypefun config_error_t config_error_type (@w{const config_t * @var{config}})
+@tindex config_error_t
+This function, which is implemented as a macro, returns the type of
+error that occurred during the last call to one of the read or write
+functions. The @var{config_error_t} type is an enumeration with the
+following values: @code{CONFIG_ERR_NONE}, @code{CONFIG_ERR_FILE_IO},
+@code{CONFIG_ERR_PARSE}. These represent success, a file I/O error,
+and a parsing error, respectively.
+
+@end deftypefun
+
+@deftypefun void config_set_include_dir (@w{config_t *@var{config}}, @w{const char *@var{include_dir}})
+@deftypefunx {const char *} config_get_include_dir (@w{const config_t *@var{config}})
+
+@code{config_set_include_dir()} specifies the include directory,
+@var{include_dir}, relative to which the files specified in
+@samp{@@include} directives will be located for the configuration
+@var{config}. By default, there is no include directory, and all
+include files are expected to be relative to the current working
+directory. If @var{include_dir} is @code{NULL}, the default behavior
+is reinstated.
+
+For example, if the include directory is set to @file{/usr/local/etc},
+the include directive @samp{@@include "configs/extra.cfg"} would include the
+file @file{/usr/local/etc/configs/extra.cfg}.
+
+@code{config_get_include_dir()} returns the current include directory for the
+configuration @var{config}, or @code{NULL} if none is set.
+
+@end deftypefun
+
+@deftypefun void config_set_auto_convert (@w{config_t *@var{config}}, @w{int @var{flag}})
+@deftypefunx int config_get_auto_convert (@w{const config_t *@var{config}})
+
+@code{config_set_auto_convert()} enables number auto-conversion for
+the configuration @var{config} if @var{flag} is non-zero, and disables
+it otherwise. When this feature is enabled, an attempt to retrieve a
+floating point setting's value into an integer (or vice versa), or
+store an integer to a floating point setting's value (or vice versa)
+will cause the library to silently perform the necessary conversion
+(possibly leading to loss of data), rather than reporting failure. By
+default this feature is disabled.
+
+@code{config_get_auto_convert()} returns @code{CONFIG_TRUE} if number
+auto-conversion is currently enabled for @var{config}; otherwise it
+returns @code{CONFIG_FALSE}.
+
+@end deftypefun
+
+@deftypefun void config_set_default_format (@w{config_t * @var{config}}, @w{short @var{format}})
+@deftypefunx short config_get_default_format (@w{config_t * @var{config}})
+
+These functions, which are implemented as macros, set and get the
+default external format for settings in the configuration
+@var{config}. If a non-default format has not been set for a setting
+with @code{config_setting_set_format()}, this configuration-wide
+default format will be used instead when that setting is written to a
+file or stream.
+
+@end deftypefun
+
+@deftypefun void config_set_tab_width (@w{config_t * @var{config}}, @w{unsigned short @var{width}})
+@deftypefunx {unsigned short} config_get_tab_width (@w{const config_t * @var{config}})
+
+These functions, which are implemented as macros, set and get the tab
+width for the configuration @var{config}. The tab width affects the
+formatting of the configuration when it is written to a file or
+stream: each level of nesting is indented by @var{width} spaces, or
+by a single tab character if @var{width} is 0. The tab width has no
+effect on parsing.
+
+Valid tab widths range from 0 to 15. The default tab width is 2.
+
+@end deftypefun
+
+@deftypefun int config_lookup_int (@w{const config_t * @var{config}}, @w{const char * @var{path}}, @w{int * @var{value}})
+@deftypefunx int config_lookup_int64 (@w{const config_t * @var{config}}, @w{const char * @var{path}}, @w{long long * @var{value}})
+@deftypefunx int config_lookup_float (@w{const config_t * @var{config}}, @w{const char * @var{path}}, @w{double * @var{value}})
+@deftypefunx int config_lookup_bool (@w{const config_t * @var{config}}, @w{const char * @var{path}}, @w{int * @var{value}})
+@deftypefunx int config_lookup_string (@w{const config_t * @var{config}}, @w{const char * @var{path}}, @w{const char ** @var{value}})
+
+These functions look up the value of the setting in the configuration
+@var{config} specified by the path @var{path}. They store the value of
+the setting at @var{value} and return @code{CONFIG_TRUE} on
+success. If the setting was not found or if the type of the value did
+not match the type requested, they leave the data pointed to by
+@var{value} unmodified and return @code{CONFIG_FALSE}.
+
+Storage for the string returned by @code{config_lookup_string()} is
+managed by the library and released automatically when the setting is
+destroyed or when the setting's value is changed; the string must not
+be freed by the caller.
+
+@end deftypefun
+
+@deftypefun {config_setting_t *} config_lookup (@w{const config_t * @var{config}}, @w{const char * @var{path}})
+
+This function locates the setting in the configuration @var{config}
+specified by the path @var{path}. It returns a pointer to the
+@code{config_setting_t} structure on success, or @code{NULL} if the
+setting was not found.
+
+@end deftypefun
+
+@deftypefun int config_setting_get_int (@w{const config_setting_t * @var{setting}})
+@deftypefunx {long long} config_setting_get_int64 (@w{const config_setting_t * @var{setting}})
+@deftypefunx double config_setting_get_float (@w{const config_setting_t * @var{setting}})
+@deftypefunx int config_setting_get_bool (@w{const config_setting_t * @var{setting}})
+@deftypefunx {const char *} config_setting_get_string (@w{const config_setting_t * @var{setting}})
+
+These functions return the value of the given @var{setting}. If the
+type of the setting does not match the type requested, a 0 or
+@code{NULL} value is returned. Storage for the string returned by
+@code{config_setting_get_string()} is managed by the library and
+released automatically when the setting is destroyed or when the
+setting's value is changed; the string must not be freed by the
+caller.
+
+@end deftypefun
+@deftypefun int config_setting_set_int (@w{config_setting_t * @var{setting}}, @w{int @var{value}})
+@deftypefunx int config_setting_set_int64 (@w{config_setting_t * @var{setting}}, @w{long long @var{value}})
+@deftypefunx int config_setting_set_float (@w{config_setting_t * @var{setting}}, @w{double @var{value}})
+@deftypefunx int config_setting_set_bool (@w{config_setting_t * @var{setting}}, @w{int @var{value}})
+@deftypefunx int config_setting_set_string (@w{config_setting_t * @var{setting}}, @w{const char * @var{value}})
+
+These functions set the value of the given @var{setting} to
+@var{value}. On success, they return @code{CONFIG_TRUE}. If
+the setting does not match the type of the value, they return
+@code{CONFIG_FALSE}. @code{config_setting_set_string()} makes a copy
+of the passed string @var{value}, so it may be subsequently freed or
+modified by the caller without affecting the value of the setting.
+
+@end deftypefun
+
+@deftypefun int config_setting_lookup_int (@w{const config_setting_t * @var{setting}}, @w{const char * @var{name}}, @w{int * @var{value}})
+@deftypefunx int config_setting_lookup_int64 (@w{const config_setting_t * @var{setting}}, @w{const char * @var{name}}, @w{long long * @var{value}})
+@deftypefunx int config_setting_lookup_float (@w{const config_setting_t * @var{setting}}, @w{const char * @var{name}}, @w{double * @var{value}})
+@deftypefunx int config_setting_lookup_bool (@w{const config_setting_t * @var{setting}}, @w{const char * @var{name}}, @w{int * @var{value}})
+@deftypefunx int config_setting_lookup_string (@w{const config_setting_t * @var{setting}}, @w{const char * @var{name}}, @w{const char ** @var{value}})
+
+These functions look up the value of the child setting named
+@var{name} of the setting @var{setting}. They store the value at
+@var{value} and return @code{CONFIG_TRUE} on success. If the setting
+was not found or if the type of the value did not match the type
+requested, they leave the data pointed to by @var{value} unmodified
+and return @code{CONFIG_FALSE}.
+
+Storage for the string returned by @code{config_setting_lookup_string()} is
+managed by the library and released automatically when the setting is
+destroyed or when the setting's value is changed; the string must not
+be freed by the caller.
+
+@end deftypefun
+
+@deftypefun short config_setting_get_format (@w{config_setting_t * @var{setting}})
+@deftypefunx int config_setting_set_format (@w{config_setting_t * @var{setting}}, @w{short @var{format}})
+
+These functions get and set the external format for the setting @var{setting}.
+
+@tindex SettingFormat
+@cindex format
+
+The @var{format} must be one of the constants
+@code{CONFIG_FORMAT_DEFAULT} or @code{CONFIG_FORMAT_HEX}. All settings
+support the @code{CONFIG_FORMAT_DEFAULT} format. The
+@code{CONFIG_FORMAT_HEX} format specifies hexadecimal formatting for
+integer values, and hence only applies to settings of type
+@code{CONFIG_TYPE_INT} and @code{CONFIG_TYPE_INT64}.  If @var{format}
+is invalid for the given setting, it is ignored.
+
+If a non-default format has not been set for the setting, @code{config_setting_get_format()} returns the default format for the configuration, as set by @code{config_set_default_format()}.
+
+@code{config_setting_set_format()} returns @code{CONFIG_TRUE} on
+success and @code{CONFIG_FALSE} on failure.
+
+@end deftypefun
+
+
+@deftypefun {config_setting_t *} config_setting_get_member (@w{config_setting_t * @var{setting}}, @w{const char * @var{name}})
+
+This function fetches the child setting named @var{name} from the group
+@var{setting}. It returns the requested setting on success, or
+@code{NULL} if the setting was not found or if @var{setting} is not a
+group.
+
+@end deftypefun
+
+@deftypefun {config_setting_t *} config_setting_get_elem (@w{const config_setting_t * @var{setting}}, @w{unsigned int @var{index}})
+
+This function fetches the element at the given index @var{index} in the
+setting @var{setting}, which must be an array, list, or group. It returns the
+requested setting on success, or @code{NULL} if @var{index} is out of
+range or if @var{setting} is not an array, list, or group.
+
+@end deftypefun
+
+@deftypefun int config_setting_get_int_elem (@w{const config_setting_t * @var{setting}}, @w{int @var{index}})
+@deftypefunx {long long} config_setting_get_int64_elem (@w{const config_setting_t * @var{setting}}, @w{int @var{index}})
+@deftypefunx double config_setting_get_float_elem (@w{const config_setting_t * @var{setting}}, @w{int @var{index}})
+@deftypefunx int config_setting_get_bool_elem (@w{const config_setting_t * @var{setting}}, @w{int @var{index}})
+@deftypefunx {const char *} config_setting_get_string_elem (@w{const config_setting_t * @var{setting}}, @w{int @var{index}})
+
+These functions return the value at the specified index @var{index} in the
+setting @var{setting}. If the setting is not an array or list, or if
+the type of the element does not match the type requested, or if
+@var{index} is out of range, they return 0 or @code{NULL}. Storage for
+the string returned by @code{config_setting_get_string_elem()} is
+managed by the library and released automatically when the setting is
+destroyed or when its value is changed; the string must not be freed
+by the caller.
+@end deftypefun
+
+@deftypefun {config_setting_t *} config_setting_set_int_elem (@w{config_setting_t * @var{setting}}, @w{int @var{index}}, @w{int @var{value}})
+@deftypefunx {config_setting_t *} config_setting_set_int64_elem (@w{config_setting_t * @var{setting}}, @w{int @var{index}}, @w{long long @var{value}})
+@deftypefunx {config_setting_t *} config_setting_set_float_elem (@w{config_setting_t * @var{setting}}, @w{int @var{index}}, @w{double @var{value}})
+@deftypefunx {config_setting_t *} config_setting_set_bool_elem (@w{config_setting_t * @var{setting}}, @w{int @var{index}}, @w{int @var{value}})
+@deftypefunx {config_setting_t *} config_setting_set_string_elem (@w{config_setting_t * @var{setting}}, @w{int @var{index}}, @w{const char * @var{value}})
+
+These functions set the value at the specified index @var{index} in the
+setting @var{setting} to @var{value}. If @var{index} is negative, a
+new element is added to the end of the array or list. On success,
+these functions return a pointer to the setting representing the
+element. If the setting is not an array or list, or if the setting is
+an array and the type of the array does not match the type of the
+value, or if @var{index} is out of range, they return
+@code{NULL}. @code{config_setting_set_string_elem()} makes a copy of
+the passed string @var{value}, so it may be subsequently freed or
+modified by the caller without affecting the value of the setting.
+@end deftypefun
+
+@deftypefun {config_setting_t *} config_setting_add (@w{config_setting_t * @var{parent}}, @w{const char * @var{name}}, @w{int @var{type}})
+
+This function adds a new child setting or element to the setting
+@var{parent}, which must be a group, array, or list. If @var{parent}
+is an array or list, the @var{name} parameter is ignored and may be
+@code{NULL}.
+
+The function returns the new setting on success, or @code{NULL} if
+@var{parent} is not a group, array, or list; or if there is already a
+child setting of @var{parent} named @var{name}; or if @var{type} is
+invalid. If @var{type} is a scalar type, the new setting will have a
+default value of 0, 0.0, @code{false}, or @code{NULL}, as appropriate.
+@end deftypefun
+
+@deftypefun int config_setting_remove (@w{config_setting_t * @var{parent}}, @w{const char * @var{name}})
+
+This function removes and destroys the setting named @var{name} from
+the parent setting @var{parent}, which must be a group. Any child
+settings of the setting are recursively destroyed as well.
+
+The function returns @code{CONFIG_TRUE} on success. If @var{parent} is
+not a group, or if it has no setting with the given name, it returns
+@code{CONFIG_FALSE}.
+
+@end deftypefun
+
+@deftypefun int config_setting_remove_elem (@w{config_setting_t * @var{parent}}, @w{unsigned int @var{index}})
+
+This function removes the child setting at the given index @var{index} from
+the setting @var{parent}, which must be a group, list, or array. Any
+child settings of the removed setting are recursively destroyed as
+well.
+
+The function returns @code{CONFIG_TRUE} on success. If @var{parent} is
+not a group, list, or array, or if @var{index} is out of range, it returns
+@code{CONFIG_FALSE}.
+
+@end deftypefun
+
+@deftypefun {config_setting_t *} config_root_setting (@w{const config_t * @var{config}})
+
+This function returns the root setting for the configuration
+@var{config}. The root setting is a group.
+
+@end deftypefun
+
+@deftypefun {const char *} config_setting_name (@w{const config_setting_t * @var{setting}})
+
+This function returns the name of the given @var{setting}, or
+@code{NULL} if the setting has no name. Storage for the returned
+string is managed by the library and released automatically when the
+setting is destroyed; the string must not be freed by the caller.
+
+@end deftypefun
+
+@deftypefun {config_setting_t *} config_setting_parent (@w{const config_setting_t * @var{setting}})
+
+This function returns the parent setting of the given @var{setting},
+or @code{NULL} if @var{setting} is the root setting.
+
+@end deftypefun
+
+@deftypefun int config_setting_is_root (@w{const config_setting_t * @var{setting}})
+
+This function returns @code{CONFIG_TRUE} if the given @var{setting} is
+the root setting, and @code{CONFIG_FALSE} otherwise.
+
+@end deftypefun
+
+@deftypefun int config_setting_index (@w{const config_setting_t * @var{setting}})
+
+This function returns the index of the given @var{setting} within its
+parent setting. If @var{setting} is the root setting, this function
+returns -1.
+
+@end deftypefun
+
+@deftypefun int config_setting_length (@w{const config_setting_t * @var{setting}})
+
+This function returns the number of settings in a group, or the number of
+elements in a list or array. For other types of settings, it returns
+0.
+
+@end deftypefun
+
+@deftypefun int config_setting_type (@w{const config_setting_t * @var{setting}})
+
+This function returns the type of the given @var{setting}. The return
+value is one of the constants
+@code{CONFIG_TYPE_INT}, @code{CONFIG_TYPE_INT64}, @code{CONFIG_TYPE_FLOAT},
+@code{CONFIG_TYPE_STRING}, @code{CONFIG_TYPE_BOOL},
+@code{CONFIG_TYPE_ARRAY}, @code{CONFIG_TYPE_LIST}, or @code{CONFIG_TYPE_GROUP}.
+
+@end deftypefun
+
+@deftypefun int config_setting_is_group (@w{const config_setting_t * @var{setting}})
+@deftypefunx int config_setting_is_array (@w{const config_setting_t * @var{setting}})
+@deftypefunx int config_setting_is_list (@w{const config_setting_t * @var{setting}})
+
+These convenience functions, which are implemented as macros, test if
+the setting @var{setting} is of a given type. They return
+@code{CONFIG_TRUE} or @code{CONFIG_FALSE}.
+
+@end deftypefun
+
+@deftypefun int config_setting_is_aggregate (@w{const config_setting_t * @var{setting}})
+@deftypefunx int config_setting_is_scalar (@w{const config_setting_t * @var{setting}})
+@deftypefunx int config_setting_is_number (@w{const config_setting_t * @var{setting}})
+
+@cindex aggregate value
+These convenience functions, which are implemented as macros, test if
+the setting @var{setting} is of an aggregate type (a group, array, or
+list), of a scalar type (integer, 64-bit integer, floating point,
+boolean, or string), and of a number (integer, 64-bit integer, or
+floating point), respectively. They return @code{CONFIG_TRUE} or
+@code{CONFIG_FALSE}.
+
+@end deftypefun
+
+@deftypefun {const char *} config_setting_source_file (@w{const config_setting_t * @var{setting}})
+
+This function returns the name of the file from which the setting
+@var{setting} was read, or NULL if the setting was not read from a
+file. This information is useful for reporting application-level
+errors. Storage for the returned string is managed by the library and
+released automatically when the configuration is destroyed; the
+string must not be freed by the caller.
+
+@end deftypefun
+
+@deftypefun {unsigned int} config_setting_source_line (@w{const config_setting_t * @var{setting}})
+
+This function returns the line number of the configuration file or
+stream at which the setting @var{setting} was read, or 0 if no line
+number is available. This information is useful for reporting
+application-level errors.
+
+@end deftypefun
+
+@deftypefun void config_setting_set_hook (@w{config_setting_t * @var{setting}}, @w{void * @var{hook}})
+@deftypefunx {void *} config_setting_get_hook (@w{const config_setting_t * @var{setting}})
+
+These functions make it possible to attach arbitrary data to each
+setting structure, for instance a ``wrapper'' or ``peer'' object written in
+another programming language. The destructor function, if one has been
+supplied via a call to @code{config_set_destructor()}, will be called
+by the library to dispose of this data when the setting itself is
+destroyed. There is no default destructor.
+
+@end deftypefun
+
+@deftypefun void config_set_destructor (@w{config_t * @var{config}}, @w{void (* @var{destructor})(void *)})
+
+This function assigns the destructor function @var{destructor} for the
+configuration @var{config}. This function accepts a single @code{void
+*} argument and has no return value. See
+@code{config_setting_set_hook()} above for more information.
+
+@end deftypefun
+
+@node The C++ API, Example Programs, The C API, Top
+@comment  node-name,  next,  previous,  up
+@chapter The C++ API
+
+@tindex Config
+@tindex Setting
+This chapter describes the C++ library API. The class @code{Config}
+represents a configuration, and the class @code{Setting} represents a
+configuration setting. Note that by design, neither of these classes
+provides a public copy constructor or assignment operator. Therefore,
+instances of these classes may only be passed between functions via
+references or pointers.
+
+@tindex ConfigException
+The library defines a group of exceptions, all of which extend the
+common base exception @code{ConfigException}.
+
+@tindex SettingTypeException
+A @code{SettingTypeException} is thrown when the type of a setting's
+value does not match the type requested.
+
+@tindex SettingNotFoundException
+A @code{SettingNotFoundException} is thrown when a setting is not found.
+
+@tindex SettingNameException
+A @code{SettingNameException} is thrown when an attempt is made to add
+a new setting with a non-unique or invalid name.
+
+@tindex ParseException
+A @code{ParseException} is thrown when a parse error occurs while
+reading a configuration from a stream.
+
+@tindex FileIOException
+A @code{FileIOException} is thrown when an I/O error occurs while
+reading/writing a configuration from/to a file.
+
+@tindex SettingException
+@code{SettingTypeException}, @code{SettingNotFoundException}, and
+@code{SettingNameException} all extend the common base
+exception @code{SettingException}, which provides the following method:
+
+@deftypemethod SettingException {const char *} getPath ()
+
+Returns the path to the setting associated with the exception, or
+@code{NULL} if there is no applicable path.
+
+@end deftypemethod
+
+The remainder of this chapter describes the methods for manipulating
+configurations and configuration settings.
+
+@deftypemethod Config {} Config ()
+@deftypemethodx Config {} ~Config ()
+
+These methods create and destroy @code{Config} objects. 
+
+@end deftypemethod
+
+@deftypemethod Config void read (@w{FILE * @var{stream}})
+@deftypemethodx Config void write (@w{FILE * @var{stream}})
+
+The @code{read()} method reads and parses a configuration from the given
+@var{stream}. A @code{ParseException} is thrown if a parse error occurs.
+
+The @code{write()} method writes the configuration to the given @var{stream}.
+
+@end deftypemethod
+
+@deftypemethod Config void readFile (@w{const char * @var{filename}})
+@deftypemethodx Config void writeFile (@w{const char * @var{filename}})
+
+The @code{readFile()} method reads and parses a configuration from the
+file named @var{filename}. A @code{ParseException} is thrown if a
+parse error occurs. A @code{FileIOException} is thrown if the file
+cannot be read.
+
+The @code{writeFile()} method writes the configuration to the file
+named @var{filename}. A @code{FileIOException} is thrown if the file cannot
+be written.
+
+@end deftypemethod
+
+@deftypemethod Config void readString (@w{const char * @var{str}})
+@deftypemethodx Config void readString (@w{const std::string &@var{str}})
+
+These methods read and parse a configuration from the string
+@var{str}. A @code{ParseException} is thrown if a parse error occurs.
+
+@end deftypemethod
+
+@deftypemethod ParseException {const char *} getError ()
+@deftypemethodx ParseException {const char *} getFile ()
+@deftypemethodx ParseException int getLine ()
+
+If a call to @code{readFile()}, @code{readString()}, or @code{read()}
+resulted in a @code{ParseException}, these methods can be called on
+the exception object to obtain the text, filename, and line number of
+the parse error. Storage for the strings returned by @code{getError()}
+and @code{getFile()} are managed by the library; the strings must not
+be freed by the caller.
+
+@end deftypemethod
+
+@deftypemethod Config void setIncludeDir (@w{const char *@var{includeDir}})
+@deftypemethodx Config {const char *} getIncludeDir ()
+
+@code{setIncludeDir()} specifies the include directory,
+@var{includeDir}, relative to which the files specified in
+@samp{@@include} directives will be located for the configuration. By
+default, there is no include directory, and all include files are
+expected to be relative to the current working directory. If
+@var{includeDir} is @code{NULL}, the default behavior is reinstated.
+
+For example, if the include directory is set to @file{/usr/local/etc},
+the include directive @samp{@@include "configs/extra.cfg"} would include the
+file @file{/usr/local/etc/configs/extra.cfg}.
+
+@code{getIncludeDir()} returns the current include directory for the
+configuration, or @code{NULL} if none is set.
+
+@end deftypemethod
+
+@deftypemethod Config void setAutoConvert (bool @var{flag})
+@deftypemethodx Config bool getAutoConvert ()
+
+@code{setAutoConvert()} enables number auto-conversion for the
+configuration if @var{flag} is @code{true}, and disables it
+otherwise. When this feature is enabled, an attempt to assign a
+floating point setting to an integer (or vice versa), or
+assign an integer to a floating point setting (or vice versa) will
+cause the library to silently perform the necessary conversion
+(possibly leading to loss of data), rather than throwing a
+@code{SettingTypeException}. By default this feature is disabled.
+
+@code{getAutoConvert()} returns @code{true} if number auto-conversion
+is currently enabled for the configuration; otherwise it returns
+@code{false}.
+
+@end deftypemethod
+
+@deftypemethod Config void setDefaultFormat (@w{Setting::Format @var{format}})
+@deftypemethodx Config Setting::Format getDefaultFormat ()
+
+These methods set and get the default external format for settings in
+the configuration. If a non-default format has not been set for a
+setting with @code{Setting::setFormat()}, this configuration-wide
+default format will be used instead when that setting is written to a
+file or stream.
+
+@end deftypemethod
+
+@deftypemethod Config void setTabWidth (@w{unsigned short @var{width}})
+@deftypemethodx Config {unsigned short} getTabWidth ()
+
+These methods set and get the tab width for the configuration. The tab
+width affects the formatting of the configuration when it is written
+to a file or stream: each level of nesting is indented by @var{width}
+spaces, or by a single tab character if @var{width} is 0. The tab
+width has no effect on parsing.
+
+Valid tab widths range from 0 to 15. The default tab width is 2.
+
+@end deftypemethod
+
+@deftypemethod Config {Setting &} getRoot ()
+
+This method returns the root setting for the configuration, which is a group.
+
+@end deftypemethod
+
+@deftypemethod Config {Setting &} lookup (@w{const std::string &@var{path}})
+@deftypemethodx Config {Setting &} lookup (@w{const char * @var{path}})
+
+These methods locate the setting specified by the path @var{path}. If
+the requested setting is not found, a @code{SettingNotFoundException} is
+thrown.
+
+@end deftypemethod
+@deftypemethod Config bool exists (@w{const std::string &@var{path}})
+@deftypemethodx Config bool exists (@w{const char *@var{path}})
+
+These methods test if a setting with the given @var{path} exists in
+the configuration. They return @code{true} if the setting exists, and
+@code{false} otherwise. These methods do not throw exceptions.
+
+@end deftypemethod
+
+@deftypemethod Config bool lookupValue (@w{const char *@var{path}}, @w{bool &@var{value}})
+@deftypemethodx Config bool lookupValue (@w{const std::string &@var{path}}, @w{bool &@var{value}})
+
+@deftypemethodx Config bool lookupValue (@w{const char *@var{path}}, @w{int &@var{value}})
+@deftypemethodx Config bool lookupValue (@w{const std::string &@var{path}}, @w{int &@var{value}})
+
+@deftypemethodx Config bool lookupValue (@w{const char *@var{path}}, @w{unsigned int &@var{value}})
+@deftypemethodx Config bool lookupValue (@w{const std::string &@var{path}}, @w{unsigned int &@var{value}})
+
+@deftypemethodx Config bool lookupValue (@w{const char *@var{path}}, @w{long long &@var{value}})
+@deftypemethodx Config bool lookupValue (@w{const std::string &@var{path}}, @w{long long &@var{value}})
+
+@deftypemethodx Config bool lookupValue (@w{const char *@var{path}}, @w{float &@var{value}})
+@deftypemethodx Config bool lookupValue (@w{const std::string &@var{path}}, @w{float &@var{value}})
+
+@deftypemethodx Config bool lookupValue (@w{const char *@var{path}}, @w{double &@var{value}})
+@deftypemethodx Config bool lookupValue (@w{const std::string &@var{path}}, @w{double &@var{value}})
+
+@deftypemethodx Config bool lookupValue (@w{const char *@var{path}}, @w{const char *&@var{value}})
+@deftypemethodx Config bool lookupValue (@w{const std::string &@var{path}}, @w{const char *&@var{value}})
+
+@deftypemethodx Config bool lookupValue (@w{const char *@var{path}}, @w{std::string &@var{value}})
+@deftypemethodx Config bool lookupValue (@w{const std::string &@var{path}}, @w{std::string &@var{value}})
+
+These are convenience methods for looking up the value of a setting
+with the given @var{path}. If the setting is found and is of an
+appropriate type, the value is stored in @var{value} and the method
+returns @code{true}. Otherwise, @var{value} is left unmodified and the
+method returns @code{false}. These methods do not throw exceptions.
+
+Storage for @w{@i{const char *}} values is managed by the library and
+released automatically when the setting is destroyed or when its value
+is changed; the string must not be freed by the caller. For safety and
+convenience, always assigning string values to a @code{std::string} is
+suggested.
+
+Since these methods have boolean return values and do not throw
+exceptions, they can be used within boolean logic expressions. The following
+example presents a concise way to look up three values at once and
+perform error handling if any of them are not found or are of the
+wrong type:
+
+@sp 1
+@cartouche
+@smallexample
+int var1;
+double var2;
+const char *var3;
+
+if(config.lookupValue("values.var1", var1)
+   && config.lookupValue("values.var2", var2)
+   && config.lookupValue("values.var3", var3))
+@{
+  // use var1, var2, var3
+@}
+else
+@{
+  // error handling here
+@}
+@end smallexample
+@end cartouche
+
+This approach also takes advantage of the short-circuit evaluation rules
+of C++, e.g., if the first lookup fails (returning @code{false}), the
+remaining lookups are skipped entirely.
+
+@end deftypemethod
+
+@deftypemethod Setting {} {operator bool ()}
+@deftypemethodx Setting {} {operator int ()}
+@deftypemethodx Setting {} {operator unsigned int ()}
+@deftypemethodx Setting {} {operator long ()}
+@deftypemethodx Setting {} {operator unsigned long ()}
+@deftypemethodx Setting {} {operator long long ()}
+@deftypemethodx Setting {} {operator unsigned long long ()}
+@deftypemethodx Setting {} {operator float ()}
+@deftypemethodx Setting {} {operator double ()}
+@deftypemethodx Setting {} {operator const char * ()}
+@deftypemethodx Setting {} {operator std::string ()}
+@deftypemethodx Setting {const char *} c_str ()
+
+These cast operators allow a @code{Setting} object to be assigned to a
+variable of type @i{bool} if it is of type @code{TypeBoolean};
+@i{int}, @i{unsigned int}; @code{long long} or @code{unsigned long long} if
+it is of type @code{TypeInt64}, @i{float} or @i{double} if it is of type
+@code{TypeFloat}; or @w{@i{const char *}} or @i{std::string} if it is
+of type @code{TypeString}.
+
+Values of type @code{TypeInt} or @code{TypeInt64} may be assigned to
+variables of type @i{long}, or @i{unsigned long}, depending on the
+sizes of those types on the host system.
+
+Storage for @w{@i{const char *}} return values is managed by the
+library and released automatically when the setting is destroyed or
+when its value is changed; the string must not be freed by the
+caller. For safety and convenience, always assigning string return
+values to a @code{std::string} is suggested.
+
+The following examples demonstrate this usage:
+
+@cartouche
+@smallexample
+long width = config.lookup("application.window.size.w");
+
+bool splashScreen = config.lookup("application.splash_screen");
+
+std::string title = config.lookup("application.window.title");
+@end smallexample
+@end cartouche
+
+Note that certain conversions can lead to loss of precision or
+clipping of values, e.g., assigning a negative value to an @i{unsigned
+int} (in which case the value will be treated as 0), or a
+double-precision value to a @i{float}. The library does not treat
+these lossy conversions as errors.
+
+Perhaps surprisingly, the following code in particular will cause a
+compiler error:
+
+@cartouche
+@smallexample
+std::string title;
+.
+.
+.
+title = config.lookup("application.window.title");
+@end smallexample
+@end cartouche
+
+This is because the assignment operator of @code{std::string} is being
+invoked with a @code{Setting &} as an argument. The compiler is unable
+to make an implicit conversion because both the @code{const char *}
+and the @code{std::string} cast operators of @code{Setting} are
+equally appropriate. This is not a bug in @i{libconfig}; providing
+only the @code{const char *} cast operator would resolve this
+particular ambiguity, but would cause assignments to
+@code{std::string} like the one in the previous example to produce a
+compiler error. (To understand why, see section 11.4.1 of @i{The C++
+Programming Language}.)
+
+The solution to this problem is to use an explicit conversion that
+avoids the construction of an intermediate @code{std::string} object,
+as follows:
+
+@cartouche
+@smallexample
+std::string title;
+.
+.
+.
+title = (const char *)config.lookup("application.window.title");
+@end smallexample
+@end cartouche
+
+Or, alternatively, use the @code{c_str()} method, which has the same effect:
+
+@cartouche
+@smallexample
+std::string title;
+.
+.
+.
+title = config.lookup("application.window.title").c_str();
+@end smallexample
+@end cartouche
+
+If the assignment is invalid due to a type mismatch, a
+@code{SettingTypeException} is thrown.
+
+@end deftypemethod
+
+@deftypemethod Setting {Setting &} operator= (@w{bool @var{value}})
+@deftypemethodx Setting {Setting &} operator= (@w{int @var{value}})
+@deftypemethodx Setting {Setting &} operator= (@w{long @var{value}})
+@deftypemethodx Setting {Setting &} operator= (@w{const long long &@var{value}})
+@deftypemethodx Setting {Setting &} operator= (@w{float @var{value}})
+@deftypemethodx Setting {Setting &} operator= (@w{const double &@var{value}})
+@deftypemethodx Setting {Setting &} operator= (@w{const char *@var{value}})
+@deftypemethodx Setting {Setting &} operator= (@w{const std::string &@var{value}})
+
+These assignment operators allow values of type @i{bool}, @i{int},
+@i{long}, @i{long long}, @i{float}, @i{double}, @i{const char *}, and
+@i{std::string} to be assigned to a setting. In the case of strings,
+the library makes a copy of the passed string @var{value}, so it may
+be subsequently freed or modified by the caller without affecting the
+value of the setting.
+
+The following example code looks up a (presumably) integer setting
+and changes its value:
+
+@cartouche
+@smallexample
+Setting &setting = config.lookup("application.window.size.w");
+setting = 1024;
+@end smallexample
+@end cartouche
+
+If the assignment is invalid due to a type mismatch, a
+@code{SettingTypeException} is thrown.
+
+@end deftypemethod
+
+@deftypemethod Setting {Setting &} {operator[]} (@w{int @var{index}})
+@deftypemethodx Setting {Setting &} {operator[]} (@w{const std::string &@var{name}})
+@deftypemethodx Setting {Setting &} {operator[]} (@w{const char *@var{name}})
+
+A @code{Setting} object may be subscripted with an integer index
+@var{index} if it is an array or list, or with either a string
+@var{name} or an integer index @var{index} if it is a group. For example,
+the following code would produce the string @samp{Last Name} when
+applied to the example configuration in @ref{Configuration Files}.
+
+@cartouche
+@smallexample
+Setting& setting = config.lookup("application.misc");
+const char *s = setting["columns"][0];
+@end smallexample
+@end cartouche
+
+If the setting is not an array, list, or group, a
+@code{SettingTypeException} is thrown. If the subscript (@var{index}
+or @var{name}) does not refer to a valid element, a
+@code{SettingNotFoundException} is thrown.
+
+Iterating over a group's child settings with an integer index will
+return the settings in the same order that they appear in the
+configuration.
+
+@end deftypemethod
+
+@deftypemethod Setting bool lookupValue (@w{const char *@var{name}}, @w{bool &@var{value}})
+@deftypemethodx Setting bool lookupValue (@w{const std::string &@var{name}}, @w{bool &@var{value}})
+
+@deftypemethodx Setting bool lookupValue (@w{const char *@var{name}}, @w{int &@var{value}})
+@deftypemethodx Setting bool lookupValue (@w{const std::string &@var{name}}, @w{int &@var{value}})
+
+@deftypemethodx Setting bool lookupValue (@w{const char *@var{name}}, @w{unsigned int &@var{value}})
+@deftypemethodx Setting bool lookupValue (@w{const std::string &@var{name}}, @w{unsigned int &@var{value}})
+
+@deftypemethodx Setting bool lookupValue (@w{const char *@var{name}}, @w{long long &@var{value}})
+@deftypemethodx Setting bool lookupValue (@w{const std::string &@var{name}}, @w{long long &@var{value}})
+
+@deftypemethodx Setting bool lookupValue (@w{const char *@var{name}}, @w{unsigned long long &@var{value}})
+@deftypemethodx Setting bool lookupValue (@w{const std::string &@var{name}}, @w{unsigned long long &@var{value}})
+
+@deftypemethodx Setting bool lookupValue (@w{const char *@var{name}}, @w{float &@var{value}})
+@deftypemethodx Setting bool lookupValue (@w{const std::string &@var{name}}, @w{float &@var{value}})
+
+@deftypemethodx Setting bool lookupValue (@w{const char *@var{name}}, @w{double &@var{value}})
+@deftypemethodx Setting bool lookupValue (@w{const std::string &@var{name}}, @w{double &@var{value}})
+
+@deftypemethodx Setting bool lookupValue (@w{const char *@var{name}}, @w{const char *&@var{value}})
+@deftypemethodx Setting bool lookupValue (@w{const std::string &@var{name}}, @w{const char *&@var{value}})
+
+@deftypemethodx Setting bool lookupValue (@w{const char *@var{name}}, @w{std::string &@var{value}})
+@deftypemethodx Setting bool lookupValue (@w{const std::string &@var{name}}, @w{std::string &@var{value}})
+
+These are convenience methods for looking up the value of a child setting
+with the given @var{name}. If the setting is found and is of an
+appropriate type, the value is stored in @var{value} and the method
+returns @code{true}. Otherwise, @var{value} is left unmodified and the
+method returns @code{false}. These methods do not throw exceptions.
+
+Storage for @w{@i{const char *}} values is managed by the library and
+released automatically when the setting is destroyed or when its value
+is changed; the string must not be freed by the caller. For safety and
+convenience, always assigning string values to a @code{std::string} is
+suggested.
+
+Since these methods have boolean return values and do not throw
+exceptions, they can be used within boolean logic expressions. The following
+example presents a concise way to look up three values at once and
+perform error handling if any of them are not found or are of the
+wrong type:
+
+@sp 1
+@cartouche
+@smallexample
+int var1;
+double var2;
+const char *var3;
+
+if(setting.lookupValue("var1", var1)
+   && setting.lookupValue("var2", var2)
+   && setting.lookupValue("var3", var3))
+@{
+  // use var1, var2, var3
+@}
+else
+@{
+  // error handling here
+@}
+@end smallexample
+@end cartouche
+
+This approach also takes advantage of the short-circuit evaluation
+rules of C++, e.g., if the first lookup fails (returning @code{false}), the
+remaining lookups are skipped entirely.
+
+@end deftypemethod
+
+@deftypemethod Setting {Setting &} add (@w{const std::string &@var{name}}, @w{Setting::Type @var{type}})
+@deftypemethodx Setting {Setting &} add (@w{const char *@var{name}}, @w{Setting::Type @var{type}})
+
+These methods add a new child setting with the given @var{name} and
+@var{type} to the setting, which must be a group. They return a
+reference to the new setting. If the setting already has a child
+setting with the given name, or if the name is invalid, a
+@code{SettingNameException} is thrown. If the setting is not a group,
+a @code{SettingTypeException} is thrown.
+
+Once a setting has been created, neither its name nor type can be
+changed.
+
+@end deftypemethod
+
+@deftypemethod Setting {Setting &} add (@w{Setting::Type @var{type}})
+
+This method adds a new element to the setting, which must be of type
+@code{TypeArray} or @code{TypeList}. If the setting is an array which
+currently has zero elements, the @var{type} parameter (which must be
+@code{TypeInt}, @code{TypeInt64}, @code{TypeFloat}, @code{TypeBool},
+or @code{TypeString}) determines the type for the array; otherwise it
+must match the type of the existing elements in the array.
+
+The method returns the new setting on success. If @var{type} is a
+scalar type, the new setting will have a default value of 0, 0.0,
+@code{false}, or @code{NULL}, as appropriate.
+
+The method throws a @code{SettingTypeException} if the setting is not
+an array or list, or if @var{type} is invalid.
+
+@end deftypemethod
+
+@deftypemethod Setting void remove (@w{const std::string &@var{name}})
+@deftypemethodx Setting void remove (@w{const char *@var{name}})
+
+These methods remove the child setting with the given @var{name} from
+the setting, which must be a group. Any child settings of the removed
+setting are recursively destroyed as well.
+
+If the setting is not a group, a @code{SettingTypeException} is
+thrown.  If the setting does not have a child setting with the given
+name, a @code{SettingNotFoundException} is thrown.
+
+@end deftypemethod
+
+@deftypemethod Setting void remove (@w{unsigned int @var{index}})
+
+This method removes the child setting at the given index @var{index} from
+the setting, which must be a group, list, or array. Any child settings
+of the removed setting are recursively destroyed as well.
+
+If the setting is not a group, list, or array, a
+@code{SettingTypeException} is thrown.  If @var{index} is out of range,
+a @code{SettingNotFoundException} is thrown.
+
+@end deftypemethod
+
+@deftypemethod Setting {const char *} getName ()
+
+This method returns the name of the setting, or @code{NULL} if the
+setting has no name. Storage for the returned string is managed by the
+library and released automatically when the setting is destroyed; the
+string must not be freed by the caller. For safety and convenience,
+consider assigning the return value to a @code{std::string}.
+
+@end deftypemethod
+
+@deftypemethod Setting {std::string} getPath ()
+
+This method returns the complete dot-separated path to the
+setting. Settings which do not have a name (list and array elements)
+are represented by their index in square brackets.
+
+@end deftypemethod
+
+@deftypemethod Setting {Setting &} getParent ()
+
+This method returns the parent setting of the setting. If the setting
+is the root setting, a @code{SettingNotFoundException} is thrown.
+
+@end deftypemethod
+
+@deftypemethod Setting bool isRoot ()
+
+This method returns @code{true} if the setting is the root setting, and
+@code{false} otherwise.
+
+@end deftypemethod
+
+@deftypemethod Setting int getIndex ()
+
+This method returns the index of the setting within its parent
+setting. When applied to the root setting, this method returns -1.
+
+@end deftypemethod
+
+@deftypemethod Setting Setting::Type getType ()
+
+@tindex Setting::Type
+This method returns the type of the setting. The
+@code{Setting::Type} enumeration consists of the following constants:
+@code{TypeInt}, @code{TypeInt64}, @code{TypeFloat}, @code{TypeString},
+@code{TypeBoolean}, @code{TypeArray}, @code{TypeList}, and
+@code{TypeGroup}.
+
+@end deftypemethod
+
+@deftypemethod Setting Setting::Format getFormat ()
+@deftypemethodx Setting void setFormat (@w{Setting::Format @var{format}})
+
+These methods get and set the external format for the setting.
+
+@tindex Setting::Format
+The @var{Setting::Format} enumeration consists of the following
+constants: @code{FormatDefault} and @code{FormatHex}. All settings
+support the @code{FormatDefault} format. The @code{FormatHex} format
+specifies hexadecimal formatting for integer values, and hence only
+applies to settings of type @code{TypeInt} and @code{TypeInt64}. If
+@var{format} is invalid for the given setting, it is ignored.
+
+@end deftypemethod
+
+@deftypemethod Setting bool exists (@w{const std::string &@var{name}})
+@deftypemethodx Setting bool exists (@w{const char *@var{name}})
+
+These methods test if the setting has a child setting with the given
+@var{name}. They return @code{true} if the setting exists, and
+@code{false} otherwise. These methods do not throw exceptions.
+
+@end deftypemethod
+
+@deftypemethod Setting int getLength ()
+
+This method returns the number of settings in a group, or the number of
+elements in a list or array. For other types of settings, it returns
+0.
+
+@end deftypemethod
+
+@deftypemethod Setting bool isGroup ()
+@deftypemethodx Setting bool isArray ()
+@deftypemethodx Setting bool isList ()
+
+These convenience methods test if a setting is of a given type.
+
+@end deftypemethod
+
+@deftypemethod Setting bool isAggregate ()
+@deftypemethodx Setting bool isScalar ()
+@deftypemethodx Setting bool isNumber ()
+
+These convenience methods test if a setting is of an aggregate type (a
+group, array, or list), of a scalar type (integer, 64-bit integer,
+floating point, boolean, or string), and of a number (integer, 64-bit
+integer, or floating point), respectively.
+
+@end deftypemethod
+
+@deftypemethod Setting {const char *} getSourceFile ()
+
+This function returns the name of the file from which the setting was
+read, or NULL if the setting was not read from a file. This
+information is useful for reporting application-level errors. Storage
+for the returned string is managed by the library and released
+automatically when the configuration is destroyed; the string must
+not be freed by the caller.
+
+@end deftypemethod
+
+@deftypemethod Setting {unsigned int} getSourceLine ()
+
+This function returns the line number of the configuration file or
+stream at which the setting @var{setting} was read, or 0 if no line
+number is available. This information is useful for reporting
+application-level errors.
+
+@end deftypemethod
+
+@node Example Programs, Configuration File Grammar, The C++ API, Top
+@comment  node-name,  next,  previous,  up
+@chapter Example Programs
+
+Practical example programs that illustrate how to use @i{libconfig}
+from both C and C++ are included in the @file{examples} subdirectory
+of the distribution. These examples include:
+
+@table @file
+
+@item examples/c/example1.c
+An example C program that reads a configuration from an existing file
+@file{example.cfg} (also located in @file{examples/c}) and displays
+some of its contents.
+
+@item examples/c++/example1.cpp
+The C++ equivalent of @file{example1.c}.
+
+@item examples/c/example2.c
+An example C program that reads a configuration from an existing file
+@file{example.cfg} (also located in @file{examples/c}), adds new
+settings to the configuration, and writes the updated configuration to
+another file.
+
+@item examples/c++/example2.cpp
+The C++ equivalent of @file{example2.c}
+
+@item examples/c/example3.c
+An example C program that constructs a new configuration in memory and writes it to a file.
+
+@item examples/c++/example3.cpp
+The C++ equivalent of @file{example3.c}
+
+@end table
+
+@node Configuration File Grammar, License, Example Programs, Top
+@comment  node-name,  next,  previous,  up
+@chapter Configuration File Grammar
+
+Below is the BNF grammar for configuration files. Comments and include
+directives are not part of the grammar, so they are not included here.
+
+@sp 1
+@example
+configuration = setting-list | empty
+
+setting-list = setting | setting-list setting
+
+setting = name (":" | "=") value (";" | "," | empty)
+
+value = scalar-value | array | list | group
+
+value-list = value | value-list "," value
+
+scalar-value = boolean | integer | integer64 | hex | hex64 | float
+               | string
+
+scalar-value-list = scalar-value | scalar-value-list "," scalar-value
+
+array = "[" (scalar-value-list | empty) "]"
+
+list = "(" (value-list | empty) ")"
+
+group = "@{" (setting-list | empty) "@}"
+
+empty =
+@end example
+
+@sp 2
+Terminals are defined below as regular expressions:
+@sp 1
+
+@multitable @columnfractions .2 .8
+@item @code{boolean} @tab
+@code{([Tt][Rr][Uu][Ee])|([Ff][Aa][Ll][Ss][Ee])}
+@item @code{string} @tab
+@code{\"([^\"\\]|\\.)*\"}
+@item @code{name} @tab
+@code{[A-Za-z\*][-A-Za-z0-9_\*]*}
+@item @code{integer} @tab
+@code{[-+]?[0-9]+}
+@item @code{integer64} @tab
+@code{[-+]?[0-9]+L(L)?}
+@item @code{hex} @tab
+@code{0[Xx][0-9A-Fa-f]+}
+@item @code{hex64} @tab
+@code{0[Xx][0-9A-Fa-f]+L(L)?}
+@item @code{float} @tab
+@code{([-+]?([0-9]*)?\.[0-9]*([eE][-+]?[0-9]+)?)|([-+]([0-9]+)(\.[0-9]*)?[eE][-+]?[0-9]+)}
+@end multitable
+
+@node License, Function Index, Configuration File Grammar, Top
+@comment  node-name,  next,  previous,  up
+@appendix License
+
+@include LGPL.texi
+
+@node Function Index, Type Index, License, Top
+@comment  node-name,  next,  previous,  up
+@unnumbered Function Index
+
+@printindex fn
+
+@node Type Index, Concept Index, Function Index, Top
+@comment  node-name,  next,  previous,  up
+@unnumbered Type Index
+
+@printindex tp
+
+@node Concept Index, , Type Index, Top
+@comment  node-name,  next,  previous,  up
+@unnumbered Concept Index
+
+@printindex cp
+
+@bye