## Version Information Version Information — variables and functions to check the GLib version |

## Synopsis

    #include <glib.h>

    extern const guint  glib_major_version;
    extern const guint  glib_minor_version;
    extern const guint  glib_micro_version;
    extern const guint  glib_binary_age;
    extern const guint  glib_interface_age;
    const gchar *       glib_check_version                  (guint required_major,
                                                             guint required_minor,
                                                             guint required_micro);

    #define             GLIB_MAJOR_VERSION
    #define             GLIB_MINOR_VERSION
    #define             GLIB_MICRO_VERSION
    #define             GLIB_CHECK_VERSION                  (major,
                                                             minor,
                                                             micro)

    #define             GLIB_VERSION_2_26
    #define             GLIB_VERSION_2_28
    #define             GLIB_VERSION_2_30
    #define             GLIB_VERSION_2_32
    #define             GLIB_VERSION_MIN_REQUIRED
    #define             GLIB_VERSION_MAX_ALLOWED
    #define             GLIB_DISABLE_DEPRECATION_WARNINGS

## Description

GLib provides version information, primarily useful in configure checks for builds that have a configure script. Applications will not typically use the features described here.

The GLib headers annotate deprecated APIs in a way that produces compiler warnings if these deprecated APIs are used. The warnings can be turned off by defining the macro `GLIB_DISABLE_DEPRECATION_WARNINGS` before including the glib.h header.

GLib also provides support for building applications against defined subsets of deprecated or new GLib APIs. Define the macro `GLIB_VERSION_MIN_REQUIRED` to specify up to what version of GLib you want to receive warnings about deprecated APIs. Define the macro `GLIB_VERSION_MAX_ALLOWED` to specify the newest version of GLib whose API you want to use.

## Details

### glib_major_version

    extern const guint glib_major_version;

### glib_minor_version

    extern const guint glib_minor_version;

### glib_micro_version

    extern const guint glib_micro_version;

### glib_binary_age

    extern const guint glib_binary_age;

### glib_interface_age

    extern const guint glib_interface_age;

### glib_check_version ()

    const gchar *       glib_check_version                  (guint required_major,
                                                             guint required_minor,
                                                             guint required_micro);

Checks that the GLib library in use is compatible with the given version. Generally you would pass in the constants GLIB_MAJOR_VERSION, GLIB_MINOR_VERSION, GLIB_MICRO_VERSION as the three arguments to this function; that produces a check that the library in use is compatible with the version of GLib the application or module was compiled against.

Compatibility is defined by two things: first the version of the running library is newer than the version `required_major.required_minor`.`required_micro`. Second the running library must be binary compatible with the version `required_major.required_minor`.`required_micro` (same major version.)

`required_major` : | the required major version.
`required_minor` : | the required minor version.
`required_micro` : | the required micro version.
Returns : | `NULL` if the GLib library is compatible with the given version, or a string describing the version mismatch. The returned string is owned by GLib and must not be modified or freed.

Since 2.6

### GLIB_MAJOR_VERSION

    #define GLIB_MAJOR_VERSION 2

The major version number of the GLib library.

Like glib_major_version, but from the headers used at application compile time, rather than from the library linked against at application run time.

### GLIB_MINOR_VERSION

    #define GLIB_MINOR_VERSION 34

The minor version number of the GLib library.

Like gtk_minor_version, but from the headers used at application compile time, rather than from the library linked against at application run time.

### GLIB_MICRO_VERSION

    #define GLIB_MICRO_VERSION 3

The micro version number of the GLib library.

Like gtk_micro_version, but from the headers used at application compile time, rather than from the library linked against at application run time.

### GLIB_CHECK_VERSION()

    #define             GLIB_CHECK_VERSION(major,minor,micro)

Checks the version of the GLib library that is being compiled against.

Example 1. Checking the version of the GLib library

    1
    2
    if (!GLIB_CHECK_VERSION (1, 2, 0))
      g_error ("GLib version 1.2.0 or above is needed");

See `glib_check_version()` for a runtime check.

`major` : | the major version to check for
`minor` : | the minor version to check for
`micro` : | the micro version to check for
Returns : | `TRUE` if the version of the GLib header files is the same as or newer than the passed-in version.

### GLIB_VERSION_2_26

    #define GLIB_VERSION_2_26       (G_ENCODE_VERSION (2, 26))

A macro that evaluates to the 2.26 version of GLib, in a format that can be used by the C pre-processor.

Since 2.32

### GLIB_VERSION_2_28

    #define GLIB_VERSION_2_28       (G_ENCODE_VERSION (2, 28))

A macro that evaluates to the 2.28 version of GLib, in a format that can be used by the C pre-processor.

Since 2.32

### GLIB_VERSION_2_30

    #define GLIB_VERSION_2_30       (G_ENCODE_VERSION (2, 30))

A macro that evaluates to the 2.30 version of GLib, in a format that can be used by the C pre-processor.

Since 2.32

### GLIB_VERSION_2_32

    #define GLIB_VERSION_2_32       (G_ENCODE_VERSION (2, 32))

A macro that evaluates to the 2.32 version of GLib, in a format that can be used by the C pre-processor.

Since 2.32

### GLIB_VERSION_MIN_REQUIRED

    # define GLIB_VERSION_MIN_REQUIRED      (GLIB_VERSION_CUR_STABLE)

A macro that should be defined by the user prior to including the glib.h header. The definition should be one of the predefined GLib version macros: `GLIB_VERSION_2_26`, `GLIB_VERSION_2_28`,...

This macro defines the earliest version of GLib that the package is required to be able to compile against.

If the compiler is configured to warn about the use of deprecated functions, then using functions that were deprecated in version `GLIB_VERSION_MIN_REQUIRED` or earlier will cause warnings (but using functions deprecated in later releases will not).

Since 2.32

### GLIB_VERSION_MAX_ALLOWED

    # define GLIB_VERSION_MAX_ALLOWED      (GLIB_VERSION_CUR_STABLE)

A macro that should be defined by the user prior to including the glib.h header. The definition should be one of the predefined GLib version macros: `GLIB_VERSION_2_26`, `GLIB_VERSION_2_28`,...

This macro defines the latest version of the GLib API that the package is allowed to make use of.

If the compiler is configured to warn about the use of deprecated functions, then using functions added after version `GLIB_VERSION_MAX_ALLOWED` will cause warnings.

Unless you are using `GLIB_CHECK_VERSION()` or the like to compile different code depending on the GLib version, then this should be set to the same value as `GLIB_VERSION_MIN_REQUIRED`.

Since 2.32

### GLIB_DISABLE_DEPRECATION_WARNINGS

    #ifdef GLIB_DISABLE_DEPRECATION_WARNINGS

A macro that should be defined before including the glib.h header. If it is defined, no compiler warnings will be produced for uses of deprecated GLib APIs.