This is libconfig.info, produced by makeinfo version 4.11 from libconfig.texi. INFO-DIR-SECTION Software libraries START-INFO-DIR-ENTRY * libconfig: (libconfig). A Library For Processing Structured Configuration Files END-INFO-DIR-ENTRY  File: libconfig.info, Node: Top, Next: Introduction, Up: (dir) libconfig ********* * Menu: * Introduction:: * Configuration Files:: * The C API:: * The C++ API:: * Configuration File Grammar:: * License:: * Function Index:: * Type Index:: * Concept Index::  File: libconfig.info, Node: Introduction, Next: Configuration Files, Prev: Top, Up: Top * 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:: 1 Introduction ************** 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).  File: libconfig.info, Node: Why Another Configuration File Library?, Next: Using the Library from a C Program, Up: Introduction 1.1 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 libconfig that set it apart from the other libraries are: * A fully reentrant parser. Independent configurations can be parsed in concurrent threads at the same time. * Both C and C++ bindings, as well as hooks to allow for the creation of wrappers in other languages. * 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. * A low-footprint implementation (just 38K for the C library and 66K for the C++ library) that is suitable for memory-constrained systems. * Proper documentation.  File: libconfig.info, Node: Using the Library from a C Program, Next: Using the Library from a C++ Program, Prev: Why Another Configuration File Library?, Up: Introduction 1.2 Using the Library from a C Program ====================================== To use the library from C code, include the following preprocessor directive in your source files: #include To link with the library, specify `-lconfig' as an argument to the linker.  File: libconfig.info, Node: Using the Library from a C++ Program, Next: Multithreading Issues, Prev: Using the Library from a C Program, Up: Introduction 1.3 Using the Library from a C++ Program ======================================== To use the library from C++, include the following preprocessor directive in your source files: #include Or, alternatively: #include The C++ API classes are defined in the namespace `libconfig', hence the following statement may optionally be used: using namespace libconfig; To link with the library, specify `-lconfig++' as an argument to the linker.  File: libconfig.info, Node: Multithreading Issues, Next: Internationalization Issues, Prev: Using the Library from a C++ Program, Up: Introduction 1.4 Multithreading Issues ========================= Libconfig is fully "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. Libconfig is not "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. Libconfig is not "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. Libconfig is not guaranteed to be "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 these C library routines are cancel-safe or not depends on the host system.  File: libconfig.info, Node: Internationalization Issues, Next: Compiling Using pkg-config, Prev: Multithreading Issues, Up: Introduction 1.5 Internationalization Issues =============================== 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 (wchar_t) strings using the wide string conversion functions such as mbsrtowcs() and wcsrtombs() or the iconv() function of the libiconv library. The textual representation of a floating point value varies by locale. However, the 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, libconfig temporarily changes the 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 libconfig in this environment, the calling program is responsible for changing the LC_NUMERIC category of the locale to the "C" locale before reading or writing a configuration.  File: libconfig.info, Node: Compiling Using pkg-config, Prev: Internationalization Issues, Up: Introduction 1.6 Compiling Using pkg-config ============================== On UNIX systems you can use the pkg-config utility (version 0.20 or later) to automatically select the appropriate compiler and linker switches for libconfig. Ensure that the environment variable `PKG_CONFIG_PATH' contains the absolute path to the `lib/pkgconfig' subdirectory of the libconfig installation. Then, you can link C programs with libconfig as follows: gcc `pkg-config --cflags libconfig` myprogram.c -o myprogram \ `pkg-config --libs libconfig` And similarly, for C++ programs: g++ `pkg-config --cflags libconfig++` myprogram.cpp -o myprogram \ `pkg-config --libs libconfig++` Note the backticks in the above examples.  File: libconfig.info, Node: Configuration Files, Next: The C API, Prev: Introduction, Up: Top * Menu: * Settings:: * Groups:: * Arrays:: * Lists:: * Integer Values:: * 64-bit Integer Values:: * Floating Point Values:: * Boolean Values:: * String Values:: * Comments:: 2 Configuration Files ********************* Libconfig supports structured, hierarchical configurations. These configurations can be read from and written to files and manipulated in memory. A "configuration" consists of a group of "settings", which associate names with values. A "value" can be one of the following: * A "scalar value": integer, 64-bit integer, floating-point number, boolean, or string * An "array", which is a sequence of scalar values, all of which must have the same type * A "group", which is a collection of settings * A "list", which is a sequence of values of any type, including other lists Consider the following configuration file for a hypothetical GUI application, which illustrates all of the elements of the configuration file grammar. # 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; }; }; Settings can be uniquely identified within the configuration by a "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 `x' setting is `application.window.pos.x'; the path to the `version' setting is simply `version'; and the path to the `title' setting of the second book in the `books' list is `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 `TRUE', `true', `FALSE', or `false' (or any other mixed-case version of those tokens, e.g., `True' or `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 conditions is considered invalid and results in a parse error. All names are case-sensitive. They may consist only of alphanumeric characters, dashes (`-'), underscores (`_'), and asterisks (`*'), 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 `long', `long long', `double', and `const char *', respectively. The boolean type is mapped to `int' in C and `bool' in C++. The following sections describe the elements of the configuration file grammar in additional detail.  File: libconfig.info, Node: Settings, Next: Groups, Up: Configuration Files 2.1 Settings ============ A setting has the form: name = value ; or: name : value ; The trailing semicolon is required. Whitespace is not significant. The value may be a scalar value, an array, a group, or a list.  File: libconfig.info, Node: Groups, Next: Arrays, Prev: Settings, Up: Configuration Files 2.2 Groups ========== A group has the form: { settings ... } Groups can contain any number of settings, but each setting must have a unique name within the group.  File: libconfig.info, Node: Arrays, Next: Lists, Prev: Groups, Up: Configuration Files 2.3 Arrays ========== An array has the form: [ value, value ... ] An array may have zero or more elements, but the elements must all be scalar values of the same type.  File: libconfig.info, Node: Lists, Next: Integer Values, Prev: Arrays, Up: Configuration Files 2.4 Lists ========= A list has the form: ( value, value ... ) A list may have zero or more elements, each of which can be a scalar value, an array, a group, or another list.  File: libconfig.info, Node: Integer Values, Next: 64-bit Integer Values, Prev: Lists, Up: Configuration Files 2.5 Integer Values ================== Integers can be represented in one of two ways: as a series of one or more decimal digits (`0' - `9'), with an optional leading sign character (`+' or `-'); or as a hexadecimal value consisting of the characters `0x' followed by a series of one or more hexadecimal digits (`0' - `9', `A' - `F', `a' - `f').  File: libconfig.info, Node: 64-bit Integer Values, Next: Floating Point Values, Prev: Integer Values, Up: Configuration Files 2.6 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, `0L' indicates a 64-bit integer value 0.  File: libconfig.info, Node: Floating Point Values, Next: Boolean Values, Prev: 64-bit Integer Values, Up: Configuration Files 2.7 Floating Point Values ========================= Floating point values consist of a series of one or more digits, one decimal point, an optional leading sign character (`+' or `-'), and an optional exponent. An exponent consists of the letter `E' or `e', an optional sign character, and a series of one or more digits.  File: libconfig.info, Node: Boolean Values, Next: String Values, Prev: Floating Point Values, Up: Configuration Files 2.8 Boolean Values ================== Boolean values may have one of the following values: `true', `false', or any mixed-case variation thereof.  File: libconfig.info, Node: String Values, Next: Comments, Prev: Boolean Values, Up: Configuration Files 2.9 String Values ================= String values consist of arbitrary text delimited by double quotes. Literal double quotes can be escaped by preceding them with a backslash: `\"'. The escape sequences `\\', `\f', `\n', `\r', and `\t' are also recognized, and have the usual meaning. 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: * `"The quick brown fox jumped over the lazy dog."' * `"The quick brown fox"' `" jumped over the lazy dog."' * `"The quick" /* comment */ " brown fox " // another comment' `"jumped over the lazy dog."'  File: libconfig.info, Node: Comments, Prev: String Values, Up: Configuration Files 2.10 Comments ============= Three types of comments are allowed within a configuration: * Script-style comments. All text beginning with a `#' character to the end of the line is ignored. * C-style comments. All text, including line breaks, between a starting `/*' sequence and an ending `*/' sequence is ignored. * C++-style comments. All text beginning with a `//' sequence to the end of the line is ignored. 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.  File: libconfig.info, Node: The C API, Next: The C++ API, Prev: Configuration Files, Up: Top 3 The C API *********** This chapter describes the C library API. The type config_t represents a configuration, and the type config_setting_t represents a configuration setting. The boolean values `CONFIG_TRUE' and `CONFIG_FALSE' are macros defined as `(1)' and `(0)', respectively. -- Function: void config_init (config_t * CONFIG) -- Function: void config_destroy (config_t * CONFIG) These functions initialize and destroy the configuration object CONFIG. `config_init()' initializes CONFIG as a new, empty configuration. `config_destroy()' destroys the configuration CONFIG, deallocating all memory associated with the configuration, but not including the config_t structure itself. -- Function: int config_read (config_t * CONFIG, FILE * STREAM) This function reads and parses a configuration from the given STREAM into the configuration object CONFIG. It returns `CONFIG_TRUE' on success, or `CONFIG_FALSE' on failure; the `config_error_text()' and `config_error_line()' functions, described below, can be used to obtain information about the error. -- Function: int config_read_file (config_t * CONFIG, const char * FILENAME) This function reads and parses a configuration from the file named FILENAME into the configuration object CONFIG. It returns `CONFIG_TRUE' on success, or `CONFIG_FALSE' on failure; the `config_error_text()' and `config_error_line()' functions, described below, can be used to obtain information about the error. -- Function: void config_write (const config_t * CONFIG, FILE * STREAM) This function writes the configuration CONFIG to the given STREAM. -- Function: int config_write_file (config_t * CONFIG, const char * FILENAME) This function writes the configuration CONFIG to the file named FILENAME. It returns `CONFIG_TRUE' on success, or `CONFIG_FALSE' on failure. -- Function: const char * config_error_text (const config_t * CONFIG) -- Function: int config_error_line (const config_t * CONFIG) These functions, which are implemented as macros, return the text and line number of the parse error, if one occurred during a call to `config_read()' or `config_read_file()'. Storage for the string returned by `config_error_text()' is managed by the library and released automatically when the configuration is destroyed; the string must not be freed by the caller. -- Function: void config_set_auto_convert (config_t *CONFIG, int FLAG) -- Function: int config_get_auto_convert (const config_t *CONFIG) `config_set_auto_convert()' enables number auto-conversion for the configuration CONFIG if 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. `config_get_auto_convert()' returns `CONFIG_TRUE' if number auto-conversion is currently enabled for CONFIG; otherwise it returns `CONFIG_FALSE'. -- Function: long config_lookup_int (const config_t * CONFIG, const char * PATH) -- Function: long long config_lookup_int64 (const config_t * CONFIG, const char * PATH) -- Function: double config_lookup_float (const config_t * CONFIG, const char * PATH) -- Function: int config_lookup_bool (const config_t * CONFIG, const char * PATH) -- Function: const char * config_lookup_string (const config_t * CONFIG, const char * PATH) These functions locate the setting in the configuration CONFIG specified by the path PATH. They return the value of the setting on success, or a 0 or `NULL' value if the setting was not found or if the type of the value did not match the type requested. Storage for the string returned by `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. -- Function: config_setting_t * config_lookup (const config_t * CONFIG, const char * PATH) This function locates the setting in the configuration CONFIG specified by the path PATH. It returns a pointer to the `config_setting_t' structure on success, or `NULL' if the setting was not found. -- Function: long config_setting_get_int (const config_setting_t * SETTING) -- Function: long long config_setting_get_int64 (const config_setting_t * SETTING) -- Function: double config_setting_get_float (const config_setting_t * SETTING) -- Function: int config_setting_get_bool (const config_setting_t * SETTING) -- Function: const char * config_setting_get_string (const config_setting_t * SETTING) These functions return the value of the given SETTING. If the type of the setting does not match the type requested, a 0 or `NULL' value is returned. Storage for the string returned by `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. -- Function: int config_setting_set_int (config_setting_t * SETTING, long VALUE) -- Function: int config_setting_set_int64 (config_setting_t * SETTING, long long VALUE) -- Function: int config_setting_set_float (config_setting_t * SETTING, double VALUE) -- Function: int config_setting_set_bool (config_setting_t * SETTING, int VALUE) -- Function: int config_setting_set_string (config_setting_t * SETTING, const char * VALUE) These functions set the value of the given SETTING to VALUE. On success, they return `CONFIG_TRUE'. If the setting does not match the type of the value, they return `CONFIG_FALSE'. `config_setting_set_string()' makes a copy of the passed string VALUE, so it may be subsequently freed or modified by the caller without affecting the value of the setting. -- Function: short config_setting_get_format (config_setting_t * SETTING) -- Function: int config_setting_set_format (config_setting_t * SETTING, short FORMAT) These functions get and set the external format for the setting SETTING. The FORMAT must be one of the constants `CONFIG_FORMAT_DEFAULT' or `CONFIG_FORMAT_HEX'. All settings support the `CONFIG_FORMAT_DEFAULT' format. The `CONFIG_FORMAT_HEX' format specifies hexadecimal formatting for integer values, and hence only applies to settings of type `CONFIG_TYPE_INT' and `CONFIG_TYPE_INT64'. If FORMAT is invalid for the given setting, it is ignored. `config_setting_set_format()' returns `CONFIG_TRUE' on success and `CONFIG_FALSE' on failure. -- Function: config_setting_t * config_setting_get_member (config_setting_t * SETTING, const char * NAME) This function fetches the child setting named NAME from the group SETTING. It returns the requested setting on success, or `NULL' if the setting was not found or if SETTING is not a group. -- Function: config_setting_t * config_setting_get_elem (const config_setting_t * SETTING, unsigned int IDX) This function fetches the element at the given index IDX in the setting SETTING, which must be an array, list, or group. It returns the requested setting on success, or `NULL' if IDX is out of range or if SETTING is not an array, list, or group. -- Function: long config_setting_get_int_elem (const config_setting_t * SETTING, int IDX) -- Function: long long config_setting_get_int64_elem (const config_setting_t * SETTING, int IDX) -- Function: double config_setting_get_float_elem (const config_setting_t * SETTING, int IDX) -- Function: int config_setting_get_bool_elem (const config_setting_t * SETTING, int IDX) -- Function: const char * config_setting_get_string_elem (const config_setting_t * SETTING, int IDX) These functions return the value at the specified index IDX in the setting 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 IDX is out of range, they return 0 or `NULL'. Storage for the string returned by `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. -- Function: config_setting_t * config_setting_set_int_elem (config_setting_t * SETTING, int IDX, long VALUE) -- Function: config_setting_t * config_setting_set_int64_elem (config_setting_t * SETTING, int IDX, long long VALUE) -- Function: config_setting_t * config_setting_set_float_elem (config_setting_t * SETTING, int IDX, double VALUE) -- Function: config_setting_t * config_setting_set_bool_elem (config_setting_t * SETTING, int IDX, int VALUE) -- Function: config_setting_t * config_setting_set_string_elem (config_setting_t * SETTING, int IDX, const char * VALUE) These functions set the value at the specified index IDX in the setting SETTING to VALUE. If IDX 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 IDX is out of range, they return `NULL'. `config_setting_set_string_elem()' makes a copy of the passed string VALUE, so it may be subsequently freed or modified by the caller without affecting the value of the setting. -- Function: config_setting_t * config_setting_add (config_setting_t * PARENT, const char * NAME, int TYPE) This function adds a new child setting or element to the setting PARENT, which must be a group, array, or list. If PARENT is an array or list, the NAME parameter is ignored and may be `NULL'. The function returns the new setting on success, or `NULL' if PARENT is not a group, array, or list; or if there is already a child setting of PARENT named NAME; or if TYPE is invalid. -- Function: int config_setting_remove (config_setting_t * PARENT, const char * NAME) This function removes and destroys the setting named NAME from the parent setting PARENT, which must be a group. Any child settings of the setting are recursively destroyed as well. The function returns `CONFIG_TRUE' on success. If PARENT is not a group, or if it has no setting with the given name, it returns `CONFIG_FALSE'. -- Function: int config_setting_remove_elem (config_setting_t * PARENT, unsigned int IDX) This function removes the child setting at the given index IDX from the setting PARENT, which must be a group, list, or array. Any child settings of the removed setting are recursively destroyed as well. The function returns `CONFIG_TRUE' on success. If PARENT is not a group, list, or array, or if IDX is out of range, it returns `CONFIG_FALSE'. -- Function: config_setting_t * config_root_setting (const config_t * CONFIG) This function returns the root setting for the configuration CONFIG. The root setting is a group. -- Function: const char * config_setting_name (const config_setting_t * SETTING) This function returns the name of the given SETTING, or `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. -- Function: config_setting_t * config_setting_parent (const config_setting_t * SETTING) This function returns the parent setting of the given SETTING, or `NULL' if SETTING is the root setting. -- Function: int config_setting_is_root (const config_setting_t * SETTING) This function returns `CONFIG_TRUE' if the given SETTING is the root setting, and `CONFIG_FALSE' otherwise. -- Function: int config_setting_index (const config_setting_t * SETTING) This function returns the index of the given SETTING within its parent setting. If SETTING is the root setting, this function returns -1. -- Function: int config_setting_length (const config_setting_t * 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. -- Function: int config_setting_type (const config_setting_t * SETTING) This function returns the type of the given SETTING. The return value is one of the constants `CONFIG_TYPE_INT', `CONFIG_TYPE_INT64', `CONFIG_TYPE_FLOAT', `CONFIG_TYPE_STRING', `CONFIG_TYPE_BOOL', `CONFIG_TYPE_ARRAY', `CONFIG_TYPE_LIST', or `CONFIG_TYPE_GROUP'. -- Function: int config_setting_is_group (const config_setting_t * SETTING) -- Function: int config_setting_is_array (const config_setting_t * SETTING) -- Function: int config_setting_is_list (const config_setting_t * SETTING) These convenience functions, which are implemented as macros, test if the setting SETTING is of a given type. They return `CONFIG_TRUE' or `CONFIG_FALSE'. -- Function: int config_setting_is_aggregate (const config_setting_t * SETTING) -- Function: int config_setting_is_scalar (const config_setting_t * SETTING) -- Function: int config_setting_is_number (const config_setting_t * SETTING) These convenience functions, which are implemented as macros, test if the setting 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 `CONFIG_TRUE' or `CONFIG_FALSE'. -- Function: unsigned int config_setting_source_line (const config_setting_t * SETTING) This function returns the line number of the configuration file or stream at which the setting SETTING was parsed. This information is useful for reporting application-level errors. If the setting was not read from a file or stream, or if the line number is otherwise unavailable, the function returns 0. -- Function: void config_setting_set_hook (config_setting_t * SETTING, void * HOOK) -- Function: void * config_setting_get_hook (const config_setting_t * 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 `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. -- Function: void config_set_destructor (config_t * CONFIG, void (* DESTRUCTOR)(void *)) This function assigns the destructor function DESTRUCTOR for the configuration CONFIG. This function accepts a single `void *' argument and has no return value. See `config_setting_set_hook()' above for more information.  File: libconfig.info, Node: The C++ API, Next: Configuration File Grammar, Prev: The C API, Up: Top 4 The C++ API ************* This chapter describes the C++ library API. The class `Config' represents a configuration, and the class `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. The library defines a group of exceptions, all of which extend the common base exception `ConfigException'. A `SettingTypeException' is thrown when the type of a setting's value does not match the type requested. A `SettingNotFoundException' is thrown when a setting is not found. A `SettingNameException' is thrown when an attempt is made to add a new setting with a non-unique or invalid name. A `ParseException' is thrown when a parse error occurs while reading a configuration from a stream. A `FileIOException' is thrown when an I/O error occurs while reading/writing a configuration from/to a file. `SettingTypeException', `SettingNotFoundException', and `SettingNameException' all extend the common base exception `SettingException', which provides the following method: -- Method on SettingException: const char * getPath () Returns the path to the setting associated with the exception, or `NULL' if there is no applicable path. The remainder of this chapter describes the methods for manipulating configurations and configuration settings. -- Method on Config: Config () -- Method on Config: ~Config () These methods create and destroy `Config' objects. -- Method on Config: void read (FILE * STREAM) -- Method on Config: void write (FILE * STREAM) The `read()' method reads and parses a configuration from the given STREAM. A `ParseException' is thrown if a parse error occurs. The `write()' method writes the configuration to the given STREAM. -- Method on Config: void readFile (const char * FILENAME) -- Method on Config: void writeFile (const char * FILENAME) The `readFile()' method reads and parses a configuration from the file named FILENAME. A `ParseException' is thrown if a parse error occurs. A `FileIOException' is thrown if the file cannot be read. The `writeFile()' method writes the configuration to the file named FILENAME. A `FileIOException' is thrown if the file cannot be written. -- Method on ParseException: const char * getError () -- Method on ParseException: int getLine () If a call to `readFile()' or `read()' resulted in a `ParseException', these methods can be called on the exception object to obtain the text and line number of the parse error. Storage for the string returned by `getError()' is managed by the library; the string must not be freed by the caller. -- Method on Config: void setAutoConvert (bool FLAG) -- Method on Config: bool getAutoConvert () `setAutoConvert()' enables number auto-conversion for the configuration if FLAG is `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 `SettingTypeException'. By default this feature is disabled. `getAutoConvert()' returns `true' if number auto-conversion is currently enabled for the configuration; otherwise it returns `false'. -- Method on Config: Setting & getRoot () This method returns the root setting for the configuration, which is a group. -- Method on Config: Setting & lookup (const std::string &PATH) -- Method on Config: Setting & lookup (const char * PATH) These methods locate the setting specified by the path PATH. If the requested setting is not found, a `SettingNotFoundException' is thrown. -- Method on Config: bool exists (const std::string &PATH) -- Method on Config: bool exists (const char *PATH) These methods test if a setting with the given PATH exists in the configuration. They return `true' if the setting exists, and FALSE otherwise. These methods do not throw exceptions. -- Method on Config: bool lookupValue (const char *PATH, bool &VALUE) -- Method on Config: bool lookupValue (const std::string &PATH, bool &VALUE) -- Method on Config: bool lookupValue (const char *PATH, int &VALUE) -- Method on Config: bool lookupValue (const std::string &PATH, int &VALUE) -- Method on Config: bool lookupValue (const char *PATH, unsigned int &VALUE) -- Method on Config: bool lookupValue (const std::string &PATH, unsigned int &VALUE) -- Method on Config: bool lookupValue (const char *PATH, long &VALUE) -- Method on Config: bool lookupValue (const std::string &PATH, long &VALUE) -- Method on Config: bool lookupValue (const char *PATH, long long &VALUE) -- Method on Config: bool lookupValue (const std::string &PATH, long long &VALUE) -- Method on Config: bool lookupValue (const char *PATH, unsigned long &VALUE) -- Method on Config: bool lookupValue (const std::string &PATH, unsigned long &VALUE) -- Method on Config: bool lookupValue (const char *PATH, float &VALUE) -- Method on Config: bool lookupValue (const std::string &PATH, float &VALUE) -- Method on Config: bool lookupValue (const char *PATH, double &VALUE) -- Method on Config: bool lookupValue (const std::string &PATH, double &VALUE) -- Method on Config: bool lookupValue (const char *PATH, const char *&VALUE) -- Method on Config: bool lookupValue (const std::string &PATH, const char *&VALUE) -- Method on Config: bool lookupValue (const char *PATH, std::string &VALUE) -- Method on Config: bool lookupValue (const std::string &PATH, std::string &VALUE) These are convenience methods for looking up the value of a setting with the given PATH. If the setting is found and is of an appropriate type, the value is stored in VALUE and the method returns `true'. Otherwise, VALUE is left unmodified and the method returns FALSE. These methods do not throw exceptions. Storage for 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 `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: 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 } This approach also takes advantage of the short-circuit evaluation rules of C++, i.e., if the first lookup fails (returning `false'), the remaining lookups are skipped entirely. -- Method on Setting: operator bool() -- Method on Setting: operator int() -- Method on Setting: operator unsigned int() -- Method on Setting: operator long() -- Method on Setting: operator unsigned long() -- Method on Setting: operator long long() -- Method on Setting: operator unsigned long long() -- Method on Setting: operator float() -- Method on Setting: operator double() -- Method on Setting: operator const char *() -- Method on Setting: operator std::string() These cast operators allow a `Setting' object to be assigned to a variable of type bool if it is of type `TypeBoolean'; int, unsigned int, long, or unsigned long if it is of type `TypeInt'; `long long' or `unsigned long long' if it is of type `TypeInt64', float or double if it is of type `TypeFloat'; or const char * or std::string if it is of type `TypeString'. Storage for 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 `std::string' is suggested. The following examples demonstrate this usage: long width = config.lookup("application.window.size.w"); bool splashScreen = config.lookup("application.splash_screen"); std::string title = config.lookup("application.window.title"); Note that certain conversions can lead to loss of precision or clipping of values, e.g., assigning a negative value to an unsigned int (in which case the value will be treated as 0), or a double-precision value to a float. The library does not treat these lossy conversions as errors. Perhaps surprisingly, the following code in particular will cause a compiler error: std::string title; . . . title = config.lookup("application.window.title"); This is because the assignment operator of `std::string' is being invoked with a `Setting &' as an argument. The compiler is unable to make an implicit conversion because both the `const char *' and the `std::string' cast operators of `Setting' are equally appropriate. This is not a bug in libconfig; providing only the `const char *' cast operator would resolve this particular ambiguity, but would cause assignments to `std::string' like the one in the previous example to produce a compiler error. (To understand why, see section 11.4.1 of The C++ Programming Language.) The solution to this problem is to use an explicit conversion that avoids the construction of an intermediate `std::string' object, as follows: std::string title; . . . title = (const char *)config.lookup("application.window.title"); If the assignment is invalid due to a type mismatch, a `SettingTypeException' is thrown. -- Method on Setting: Setting & operator= (bool VALUE) -- Method on Setting: Setting & operator= (int VALUE) -- Method on Setting: Setting & operator= (long VALUE) -- Method on Setting: Setting & operator= (const long long &VALUE) -- Method on Setting: Setting & operator= (float VALUE) -- Method on Setting: Setting & operator= (const double &VALUE) -- Method on Setting: Setting & operator= (const char *VALUE) -- Method on Setting: Setting & operator= (const std::string &VALUE) These assignment operators allow values of type bool, int, long, long long, float, double, const char *, and std::string to be assigned to a setting. In the case of strings, the library makes a copy of the passed string VALUE, so it may be subsequently freed or modified by the caller without affecting the value of the setting. If the assignment is invalid due to a type mismatch, a `SettingTypeException' is thrown. -- Method on Setting: Setting & operator[] (int IDX) -- Method on Setting: Setting & operator[] (const std::string &NAME) -- Method on Setting: Setting & operator[] (const char *NAME) A `Setting' object may be subscripted with an integer index IDX if it is an array or list, or with either a string NAME or an integer index IDX if it is a group. For example, the following code would produce the string `Last Name' when applied to the example configuration in *note Configuration Files::. Setting& setting = config.lookup("application.misc"); const char *s = setting["columns"][0]; If the setting is not an array, list, or group, a `SettingTypeException' is thrown. If the subscript (IDX or NAME) does not refer to a valid element, a `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. -- Method on Setting: bool lookupValue (const char *NAME, bool &VALUE) -- Method on Setting: bool lookupValue (const std::string &NAME, bool &VALUE) -- Method on Setting: bool lookupValue (const char *NAME, int &VALUE) -- Method on Setting: bool lookupValue (const std::string &NAME, int &VALUE) -- Method on Setting: bool lookupValue (const char *NAME, unsigned int &VALUE) -- Method on Setting: bool lookupValue (const std::string &NAME, unsigned int &VALUE) -- Method on Setting: bool lookupValue (const char *NAME, long long &VALUE) -- Method on Setting: bool lookupValue (const std::string &NAME, long long &VALUE) -- Method on Setting: bool lookupValue (const char *NAME, unsigned long long &VALUE) -- Method on Setting: bool lookupValue (const std::string &NAME, unsigned long long &VALUE) -- Method on Setting: bool lookupValue (const char *NAME, long &VALUE) -- Method on Setting: bool lookupValue (const std::string &NAME, long &VALUE) -- Method on Setting: bool lookupValue (const char *NAME, unsigned long &VALUE) -- Method on Setting: bool lookupValue (const std::string &NAME, unsigned long &VALUE) -- Method on Setting: bool lookupValue (const char *NAME, float &VALUE) -- Method on Setting: bool lookupValue (const std::string &NAME, float &VALUE) -- Method on Setting: bool lookupValue (const char *NAME, double &VALUE) -- Method on Setting: bool lookupValue (const std::string &NAME, double &VALUE) -- Method on Setting: bool lookupValue (const char *NAME, const char *&VALUE) -- Method on Setting: bool lookupValue (const std::string &NAME, const char *&VALUE) -- Method on Setting: bool lookupValue (const char *NAME, std::string &VALUE) -- Method on Setting: bool lookupValue (const std::string &NAME, std::string &VALUE) These are convenience methods for looking up the value of a child setting with the given NAME. If the setting is found and is of an appropriate type, the value is stored in VALUE and the method returns `true'. Otherwise, VALUE is left unmodified and the method returns FALSE. These methods do not throw exceptions. Storage for 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 `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: 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 } This approach also takes advantage of the short-circuit evaluation rules of C++, e.g., if the first lookup fails (returning `false'), the remaining lookups are skipped entirely. -- Method on Setting: Setting & add (const std::string &NAME, Setting::Type TYPE) -- Method on Setting: Setting & add (const char *NAME, Setting::Type TYPE) These methods add a new child setting with the given NAME and 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 `SettingNameException' is thrown. If the setting is not a group, a `SettingTypeException' is thrown. Once a setting has been created, neither its name nor type can be changed. -- Method on Setting: Setting & add (Setting::Type TYPE) This method adds a new element to the setting, which must be of type `TypeArray' or `TypeList'. If the setting is an array which currently has zero elements, the TYPE parameter (which must be `TypeInt', `TypeInt64', `TypeFloat', `TypeBool', or `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 TYPE is a scalar type, the new setting will have a default value of 0, 0.0, `false', or `NULL', depending on the type. The method throws a `SettingTypeException' if the setting is not an array or list, or if TYPE is invalid. -- Method on Setting: void remove (const std::string &NAME) -- Method on Setting: void remove (const char *NAME) These methods remove the child setting with the given 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 `SettingTypeException' is thrown. If the setting does not have a child setting with the given name, a `SettingNotFoundException' is thrown. -- Method on Setting: void remove (unsigned int IDX) This method removes the child setting at the given index IDX 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 `SettingTypeException' is thrown. If IDX is out of range, a `SettingNotFoundException' is thrown. -- Method on Setting: const char * getName () This method returns the name of the setting, or `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 `std::string'. -- Method on 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. -- Method on Setting: Setting & getParent () This method returns the parent setting of the setting. If the setting is the root setting, a `SettingNotFoundException' is thrown. -- Method on Setting: bool isRoot () This method returns true if the setting is the root setting, and false otherwise. -- Method on 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. -- Method on Setting: Setting::Type getType () This method returns the type of the setting. The `Setting::Type' enumeration consists of the following constants: `TypeInt', `TypeInt64', `TypeFloat', `TypeString', `TypeBoolean', `TypeArray', `TypeList', or `TypeGroup'. -- Method on Setting: Setting::Format getFormat () -- Method on Setting: void setFormat (Setting::Format FORMAT) These methods get and set the external format for the setting. The SETTING::FORMAT enumeration consists of the following constants: `FormatDefault', `FormatHex'. All settings support the `FormatDefault' format. The `FormatHex' format specifies hexadecimal formatting for integer values, and hence only applies to settings of type `TypeInt' and `TypeInt64'. If FORMAT is invalid for the given setting, it is ignored. -- Method on Setting: bool exists (const std::string &NAME) -- Method on Setting: bool exists (const char *NAME) These methods test if the setting has a child setting with the given NAME. They return `true' if the setting exists, and FALSE otherwise. These methods do not throw exceptions. -- Method on 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. -- Method on Setting: bool isGroup () -- Method on Setting: bool isArray () -- Method on Setting: bool isList () These convenience methods test if a setting is of a given type. -- Method on Setting: bool isAggregate () -- Method on Setting: bool isScalar () -- Method on 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 or floating point), respectively. -- Method on Setting: unsigned int getSourceLine () This method returns the line number of the configuration file or stream at which the setting was parsed. This information is useful for reporting application-level errors. If the setting was not read from a file or stream, or if the line number is otherwise unavailable, the method returns 0.  File: libconfig.info, Node: Configuration File Grammar, Next: License, Prev: The C++ API, Up: Top 5 Configuration File Grammar **************************** Below is the BNF grammar for configuration files. Comments are not part of the grammar, and hence are not included here. configuration = setting-list | empty empty = setting-list = setting | setting-list setting setting = name (":" | "=") value ";" 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) "}" Terminals are defined below as regular expressions: `boolean' `([Tt][Rr][Uu][Ee])|([Ff][Aa][Ll][Ss][Ee])' `string' `\"([^\"\\]|\\.)*\"' `name' `[A-Za-z\*][-A-Za-z0-9_\*]*' `integer' `[-+]?[0-9]+' `integer64' `[-+]?[0-9]+L(L)?' `hex' `0[Xx][0-9A-Fa-f]+' `hex64' `0[Xx][0-9A-Fa-f]+L(L)?' `float' `([-+]?([0-9]*)?\.[0-9]*([eE][-+]?[0-9]+)?)|([-+]([0-9]+)(\.[0-9]*)?[eE][-+]?[0-9]+)'  File: libconfig.info, Node: License, Next: Function Index, Prev: Configuration File Grammar, Up: Top Appendix A License ****************** GNU LESSER GENERAL PUBLIC LICENSE Version 2.1, February 1999 Copyright (C) 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. 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To apply these terms, attach the following notices to the library. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found. Copyright (C) This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Also add information on how to contact you by electronic and paper mail. You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the library, if necessary. Here is a sample; alter the names: Yoyodyne, Inc., hereby disclaims all copyright interest in the library `Frob' (a library for tweaking knobs) written by James Random Hacker. , 1 April 1990 Ty Coon, President of Vice That's all there is to it!  File: libconfig.info, Node: Function Index, Next: Type Index, Prev: License, Up: Top Function Index ************** [index] * Menu: * add on Setting: The C++ API. (line 378) * Config on Config: The C++ API. (line 43) * config_destroy: The C API. (line 15) * config_error_line: The C API. (line 55) * config_error_text: The C API. (line 54) * config_get_auto_convert: The C API. (line 65) * config_init: The C API. (line 14) * config_lookup: The C API. (line 102) * config_lookup_bool: The C API. (line 87) * config_lookup_float: The C API. (line 85) * config_lookup_int: The C API. (line 81) * config_lookup_int64: The C API. (line 83) * config_lookup_string: The C API. (line 89) * config_read: The C API. (line 26) * config_read_file: The C API. (line 35) * config_root_setting: The C API. (line 254) * config_set_auto_convert: The C API. (line 64) * config_set_destructor: The C API. (line 348) * config_setting_add: The C API. (line 221) * config_setting_get_bool: The C API. (line 116) * config_setting_get_bool_elem: The C API. (line 187) * config_setting_get_elem: The C API. (line 173) * config_setting_get_float: The C API. (line 114) * config_setting_get_float_elem: The C API. (line 185) * config_setting_get_format: The C API. (line 147) * config_setting_get_hook: The C API. (line 338) * config_setting_get_int: The C API. (line 110) * config_setting_get_int64: The C API. (line 112) * config_setting_get_int64_elem: The C API. (line 183) * config_setting_get_int_elem: The C API. (line 181) * config_setting_get_member: The C API. (line 166) * config_setting_get_string: The C API. (line 118) * config_setting_get_string_elem: The C API. (line 189) * config_setting_index: The C API. (line 280) * config_setting_is_aggregate: The C API. (line 313) * config_setting_is_array: The C API. (line 304) * config_setting_is_group: The C API. (line 302) * config_setting_is_list: The C API. (line 306) * config_setting_is_number: The C API. (line 317) * config_setting_is_root: The C API. (line 274) * config_setting_is_scalar: The C API. (line 315) * config_setting_length: The C API. (line 287) * config_setting_name: The C API. (line 260) * config_setting_parent: The C API. (line 268) * config_setting_remove: The C API. (line 231) * config_setting_remove_elem: The C API. (line 242) * config_setting_set_bool: The C API. (line 135) * config_setting_set_bool_elem: The C API. (line 206) * config_setting_set_float: The C API. (line 133) * config_setting_set_float_elem: The C API. (line 204) * config_setting_set_format: The C API. (line 149) * config_setting_set_hook: The C API. (line 336) * config_setting_set_int: The C API. (line 129) * config_setting_set_int64: The C API. (line 131) * config_setting_set_int64_elem: The C API. (line 202) * config_setting_set_int_elem: The C API. (line 200) * config_setting_set_string: The C API. (line 137) * config_setting_set_string_elem: The C API. (line 208) * config_setting_source_line: The C API. (line 327) * config_setting_type: The C API. (line 293) * config_write: The C API. (line 43) * config_write_file: The C API. (line 48) * exists on Config: The C++ API. (line 104) * exists on Setting: The C++ API. (line 479) * getAutoConvert on Config: The C++ API. (line 77) * getError on ParseException: The C++ API. (line 67) * getFormat on Setting: The C++ API. (line 467) * getIndex on Setting: The C++ API. (line 455) * getLength on Setting: The C++ API. (line 486) * getLine on ParseException: The C++ API. (line 68) * getName on Setting: The C++ API. (line 429) * getParent on Setting: The C++ API. (line 444) * getPath on Setting: The C++ API. (line 438) * getPath on SettingException: The C++ API. (line 35) * getRoot on Config: The C++ API. (line 92) * getSourceLine on Setting: The C++ API. (line 507) * getType on Setting: The C++ API. (line 460) * isAggregate on Setting: The C++ API. (line 498) * isArray on Setting: The C++ API. (line 493) * isGroup on Setting: The C++ API. (line 492) * isList on Setting: The C++ API. (line 494) * isNumber on Setting: The C++ API. (line 500) * isRoot on Setting: The C++ API. (line 450) * isScalar on Setting: The C++ API. (line 499) * lookup on Config: The C++ API. (line 97) * lookupValue on Config: The C++ API. (line 111) * lookupValue on Setting: The C++ API. (line 298) * operator bool() on Setting: The C++ API. (line 185) * operator const char *() on Setting: The C++ API. (line 194) * operator double() on Setting: The C++ API. (line 193) * operator float() on Setting: The C++ API. (line 192) * operator int() on Setting: The C++ API. (line 186) * operator long long() on Setting: The C++ API. (line 190) * operator long() on Setting: The C++ API. (line 188) * operator std::string() on Setting: The C++ API. (line 195) * operator unsigned int() on Setting: The C++ API. (line 187) * operator unsigned long long() on Setting: The C++ API. (line 191) * operator unsigned long() on Setting: The C++ API. (line 189) * operator= on Setting: The C++ API. (line 257) * operator[] on Setting: The C++ API. (line 276) * read on Config: The C++ API. (line 48) * readFile on Config: The C++ API. (line 56) * remove on Setting: The C++ API. (line 408) * setAutoConvert on Config: The C++ API. (line 76) * setFormat on Setting: The C++ API. (line 468) * write on Config: The C++ API. (line 49) * writeFile on Config: The C++ API. (line 57) * ~Config on Config: The C++ API. (line 44)  File: libconfig.info, Node: Type Index, Next: Concept Index, Prev: Function Index, Up: Top Type Index ********** [index] * Menu: * Config: The C++ API. (line 6) * config_setting_t: The C API. (line 6) * config_t: The C API. (line 6) * ConfigException: The C++ API. (line 13) * FileIOException: The C++ API. (line 27) * ParseException: The C++ API. (line 24) * Setting: The C++ API. (line 6) * Setting::Format: The C++ API. (line 470) * Setting::Type: The C++ API. (line 460) * SettingException: The C++ API. (line 30) * SettingFormat: The C API. (line 152) * SettingNameException: The C++ API. (line 21) * SettingNotFoundException: The C++ API. (line 19) * SettingTypeException: The C++ API. (line 16)  File: libconfig.info, Node: Concept Index, Prev: Type Index, Up: Top Concept Index ************* [index] * Menu: * aggregate value: The C API. (line 317) * array: Configuration Files. (line 23) * comment: Comments. (line 6) * configuration: Configuration Files. (line 23) * format: The C API. (line 152) * group: Configuration Files. (line 23) * list: Configuration Files. (line 23) * locale: Internationalization Issues. (line 14) * path: Configuration Files. (line 76) * scalar value: Configuration Files. (line 23) * setting: Configuration Files. (line 23) * Unicode: Internationalization Issues. (line 6) * UTF-8: Internationalization Issues. (line 6) * value: Configuration Files. (line 23)  Tag Table: Node: Top245 Node: Introduction511 Node: Why Another Configuration File Library?1323 Node: Using the Library from a C Program2399 Node: Using the Library from a C++ Program2867 Node: Multithreading Issues3532 Node: Internationalization Issues5099 Node: Compiling Using pkg-config6622 Node: Configuration Files7472 Node: Settings11301 Node: Groups11619 Node: Arrays11893 Node: Lists12165 Node: Integer Values12451 Node: 64-bit Integer Values12915 Node: Floating Point Values13294 Node: Boolean Values13751 Node: String Values14023 Node: Comments14912 Node: The C API15792 Node: The C++ API31858 Node: Configuration File Grammar53777 Node: License55074 Node: Function Index83168 Node: Type Index91197 Node: Concept Index92362  End Tag Table