Pango Reference Manual: Scripts and Languages

## Scripts and Languages Scripts and Languages — Identifying writing systems and languages |

## Functions

#define | PANGO_TYPE_SCRIPT
PangoScript | pango_script_for_unichar ()
PangoLanguage * | pango_script_get_sample_language ()
PangoScriptIter * | pango_script_iter_new ()
void | pango_script_iter_get_range ()
gboolean | pango_script_iter_next ()
void | pango_script_iter_free ()
#define | PANGO_TYPE_LANGUAGE
PangoLanguage * | pango_language_from_string ()
const char * | pango_language_to_string ()
gboolean | pango_language_matches ()
gboolean | pango_language_includes_script ()
const PangoScript * | pango_language_get_scripts ()
PangoLanguage * | pango_language_get_default ()
const char * | pango_language_get_sample_string ()

## Types and Values

enum | PangoScript
| PangoScriptIter
| PangoLanguage

## Object Hierarchy

        GBoxed
        ╰── PangoLanguage
        GEnum
        ╰── PangoScript

## Description

The functions in this section are used to identify the writing system, or script of individual characters and of ranges within a larger text string.

## Functions

### PANGO_TYPE_SCRIPT

    #define PANGO_TYPE_SCRIPT (pango_script_get_type ())

### pango_script_for_unichar ()

    PangoScript
    pango_script_for_unichar (gunichar ch);

Looks up the PangoScript for a particular character (as defined by Unicode Standard Annex #24). No check is made for `ch` being a valid Unicode character; if you pass in invalid character, the result is undefined.

As of Pango 1.18, this function simply returns the return value of `g_unichar_get_script()`.

#### Parameters

ch | a Unicode character |

#### Returns

the PangoScript for the character.

Since 1.4

### pango_script_get_sample_language ()

    PangoLanguage *
    pango_script_get_sample_language (PangoScript script);

Given a script, finds a language tag that is reasonably representative of that script. This will usually be the most widely spoken or used language written in that script: for instance, the sample language for `PANGO_SCRIPT_CYRILLIC` is `ru` (Russian), the sample language for `PANGO_SCRIPT_ARABIC` is `ar`.

For some scripts, no sample language will be returned because there is no language that is sufficiently representative. The best example of this is `PANGO_SCRIPT_HAN`, where various different variants of written Chinese, Japanese, and Korean all use significantly different sets of Han characters and forms of shared characters. No sample language can be provided for many historical scripts as well.

As of 1.18, this function checks the environment variables PANGO_LANGUAGE and LANGUAGE (checked in that order) first. If one of them is set, it is parsed as a list of language tags separated by colons or other separators. This function will return the first language in the parsed list that Pango believes may use `script` for writing. This last predicate is tested using `pango_language_includes_script()`. This can be used to control Pango's font selection for non-primary languages. For example, a PANGO_LANGUAGE enviroment variable set to "en:fa" makes Pango choose fonts suitable for Persian (fa) instead of Arabic (ar) when a segment of Arabic text is found in an otherwise non-Arabic text. The same trick can be used to choose a default language for `PANGO_SCRIPT_HAN` when setting context language is not feasible.

#### Parameters

script | a PangoScript |

#### Returns

a PangoLanguage that is representative of the script, or `NULL` if no such language exists.

Since 1.4

### pango_script_iter_new ()

    PangoScriptIter *
    pango_script_iter_new (const char *text,
                           int length);

Create a new PangoScriptIter, used to break a string of Unicode into runs by text. No copy is made of `text` , so the caller needs to make sure it remains valid until the iterator is freed with `pango_script_iter_free()`.

#### Parameters

text | a UTF-8 string |
length | length of `text` , or -1 if `text` is nul-terminated. |

#### Returns

the new script iterator, initialized to point at the first range in the text, which should be freed with `pango_script_iter_free()`. If the string is empty, it will point at an empty range.

Since 1.4

### pango_script_iter_get_range ()

    void
    pango_script_iter_get_range (PangoScriptIter *iter,
                                 const char **start,
                                 const char **end,
                                 PangoScript *script);

Gets information about the range to which `iter` currently points. The range is the set of locations p where *start <= p < *end. (That is, it doesn't include the character stored at *end)

#### Parameters

iter | a PangoScriptIter |
start | location to store start position of the range, or `NULL`. | [out][allow-none]
end | location to store end position of the range, or `NULL`. | [out][allow-none]
script | location to store script for range, or `NULL`. | [out][allow-none]

Since 1.4

### pango_script_iter_next ()

    gboolean
    pango_script_iter_next (PangoScriptIter *iter);

Advances a PangoScriptIter to the next range. If `iter` is already at the end, it is left unchanged and `FALSE` is returned.

#### Parameters

iter | a PangoScriptIter |

#### Returns

`TRUE` if `iter` was successfully advanced.

Since 1.4

### pango_script_iter_free ()

    void
    pango_script_iter_free (PangoScriptIter *iter);

Frees a PangoScriptIter created with `pango_script_iter_new()`.

#### Parameters

iter | a PangoScriptIter |

Since 1.4

### PANGO_TYPE_LANGUAGE

    #define PANGO_TYPE_LANGUAGE (pango_language_get_type ())

The GObject type for PangoLanguage.

### pango_language_from_string ()

    PangoLanguage *
    pango_language_from_string (const char *language);

Take a RFC-3066 format language tag as a string and convert it to a PangoLanguage pointer that can be efficiently copied (copy the pointer) and compared with other language tags (compare the pointer.)

This function first canonicalizes the string by converting it to lowercase, mapping '_' to '-', and stripping all characters other than letters and '-'.

Use `pango_language_get_default()` if you want to get the PangoLanguage for the current locale of the process.

#### Parameters

language | a string representing a language tag, or `NULL`. | [allow-none]

#### Returns

an opaque pointer to a PangoLanguage structure, or `NULL` if `language` was `NULL`. The returned pointer will be valid forever after, and should not be freed.

[transfer none]

### pango_language_to_string ()

    const char *
    pango_language_to_string (PangoLanguage *language);

Gets the RFC-3066 format string representing the given language tag.

#### Parameters

language | a language tag. |

#### Returns

a string representing the language tag. This is owned by Pango and should not be freed.

### pango_language_matches ()

    gboolean
    pango_language_matches (PangoLanguage *language,
                            const char *range_list);

Checks if a language tag matches one of the elements in a list of language ranges. A language tag is considered to match a range in the list if the range is '*', the range is exactly the tag, or the range is a prefix of the tag, and the character after it in the tag is '-'.

#### Parameters

language | a language tag (see `pango_language_from_string()`), `NULL` is allowed and matches nothing but '*' |
range_list | a list of language ranges, separated by ';', ':', ',', or space characters. Each element must either be '*', or a RFC 3066 language range canonicalized as by `pango_language_from_string()` |

#### Returns

`TRUE` if a match was found.

### pango_language_includes_script ()

    gboolean
    pango_language_includes_script (PangoLanguage *language,
                                    PangoScript script);

Determines if `script` is one of the scripts used to write `language` . The returned value is conservative; if nothing is known about the language tag `language` , `TRUE` will be returned, since, as far as Pango knows, `script` might be used to write `language` .

This routine is used in Pango's itemization process when determining if a supplied language tag is relevant to a particular section of text. It probably is not useful for applications in most circumstances.

This function uses `pango_language_get_scripts()` internally.

#### Parameters

language | a PangoLanguage, or `NULL` |
script | a PangoScript |

#### Returns

`TRUE` if `script` is one of the scripts used to write `language` or if nothing is known about `language` (including the case that `language` is `NULL`), `FALSE` otherwise.

Since 1.4

### pango_language_get_scripts ()

    const PangoScript *
    pango_language_get_scripts (PangoLanguage *language,
                                int *num_scripts);

Determines the scripts used to to write `language` . If nothing is known about the language tag `language` , or if `language` is `NULL`, then `NULL` is returned. The list of scripts returned starts with the script that the language uses most and continues to the one it uses least.

The value `num_script` points at will be set to the number of scripts in the returned array (or zero if `NULL` is returned).

Most languages use only one script for writing, but there are some that use two (Latin and Cyrillic for example), and a few use three (Japanese for example). Applications should not make any assumptions on the maximum number of scripts returned though, except that it is positive if the return value is not `NULL`, and it is a small number.

The `pango_language_includes_script()` function uses this function internally.

#### Parameters

language | a PangoLanguage, or `NULL`. | [allow-none]
num_scripts | location to return number of scripts, or `NULL`. | [out caller-allocates][allow-none]

#### Returns

An array of PangoScript values, with the number of entries in the array stored in `num_scripts` , or `NULL` if Pango does not have any information about this particular language tag (also the case if `language` is `NULL`). The returned array is owned by Pango and should not be modified or freed.

[array length=num_scripts]

Since 1.22

### pango_language_get_default ()

    PangoLanguage *
    pango_language_get_default (void);

Returns the PangoLanguage for the current locale of the process. Note that this can change over the life of an application.

On Unix systems, this is the return value is derived from `setlocale(LC_CTYPE, NULL)`, and the user can affect this through the environment variables LC_ALL, LC_CTYPE or LANG (checked in that order). The locale string typically is in the form lang_COUNTRY, where lang is an ISO-639 language code, and COUNTRY is an ISO-3166 country code. For instance, sv_FI for Swedish as written in Finland or pt_BR for Portuguese as written in Brazil.

On Windows, the C library does not use any such environment variables, and setting them won't affect the behavior of functions like `ctime()`. The user sets the locale through the Regional Options in the Control Panel. The C library (in the `setlocale()` function) does not use country and language codes, but country and language names spelled out in English. However, this function does check the above environment variables, and does return a Unix-style locale string based on either said environment variables or the thread's current locale.

Your application should call `setlocale(LC_ALL, "");` for the user settings to take effect. Gtk+ does this in its initialization functions automatically (by calling `gtk_set_locale()`). See `man setlocale` for more details.

#### Returns

the default language as a PangoLanguage, must not be freed.

[transfer none]

Since 1.16

### pango_language_get_sample_string ()

    const char *
    pango_language_get_sample_string (PangoLanguage *language);

Get a string that is representative of the characters needed to render a particular language.

The sample text may be a pangram, but is not necessarily. It is chosen to be demonstrative of normal text in the language, as well as exposing font feature requirements unique to the language. It is suitable for use as sample text in a font selection dialog.

If `language` is `NULL`, the default language as found by `pango_language_get_default()` is used.

If Pango does not have a sample string for `language` , the classic "The quick brown fox..." is returned. This can be detected by comparing the returned pointer value to that returned for (non-existent) language code "xx". That is, compare to:

    1
    pango_language_get_sample_string (pango_language_from_string ("xx"))

#### Parameters

language | a PangoLanguage, or `NULL` |

#### Returns

the sample string. This value is owned by Pango and should not be freed.

## Types and Values

### enum PangoScript

The PangoScript enumeration identifies different writing systems. The values correspond to the names as defined in the Unicode standard. Note that new types may be added in the future. Applications should be ready to handle unknown values. This enumeration is interchangeable with GUnicodeScript. See Unicode Standard Annex 24: Script names.

#### Members

PANGO_SCRIPT_INVALID_CODE | a value never returned from `pango_script_for_unichar()` |
PANGO_SCRIPT_COMMON | a character used by multiple different scripts |
PANGO_SCRIPT_INHERITED | a mark glyph that takes its script from the base glyph to which it is attached |
PANGO_SCRIPT_ARABIC | Arabic |
PANGO_SCRIPT_ARMENIAN | Armenian |
PANGO_SCRIPT_BENGALI | Bengali |
PANGO_SCRIPT_BOPOMOFO | Bopomofo |
PANGO_SCRIPT_CHEROKEE | Cherokee |
PANGO_SCRIPT_COPTIC | Coptic |
PANGO_SCRIPT_CYRILLIC | Cyrillic |
PANGO_SCRIPT_DESERET | Deseret |
PANGO_SCRIPT_DEVANAGARI | Devanagari |
PANGO_SCRIPT_ETHIOPIC | Ethiopic |
PANGO_SCRIPT_GEORGIAN | Georgian |
PANGO_SCRIPT_GOTHIC | Gothic |
PANGO_SCRIPT_GREEK | Greek |
PANGO_SCRIPT_GUJARATI | Gujarati |
PANGO_SCRIPT_GURMUKHI | Gurmukhi |
PANGO_SCRIPT_HAN | Han |
PANGO_SCRIPT_HANGUL | Hangul |
PANGO_SCRIPT_HEBREW | Hebrew |
PANGO_SCRIPT_HIRAGANA | Hiragana |
PANGO_SCRIPT_KANNADA | Kannada |
PANGO_SCRIPT_KATAKANA | Katakana |
PANGO_SCRIPT_KHMER | Khmer |
PANGO_SCRIPT_LAO | Lao |
PANGO_SCRIPT_LATIN | Latin |
PANGO_SCRIPT_MALAYALAM | Malayalam |
PANGO_SCRIPT_MONGOLIAN | Mongolian |
PANGO_SCRIPT_MYANMAR | Myanmar |
PANGO_SCRIPT_OGHAM | Ogham |
PANGO_SCRIPT_OLD_ITALIC | Old Italic |
PANGO_SCRIPT_ORIYA | Oriya |
PANGO_SCRIPT_RUNIC | Runic |
PANGO_SCRIPT_SINHALA | Sinhala |
PANGO_SCRIPT_SYRIAC | Syriac |
PANGO_SCRIPT_TAMIL | Tamil |
PANGO_SCRIPT_TELUGU | Telugu |
PANGO_SCRIPT_THAANA | Thaana |
PANGO_SCRIPT_THAI | Thai |
PANGO_SCRIPT_TIBETAN | Tibetan |
PANGO_SCRIPT_CANADIAN_ABORIGINAL | Canadian Aboriginal |
PANGO_SCRIPT_YI | Yi |
PANGO_SCRIPT_TAGALOG | Tagalog |
PANGO_SCRIPT_HANUNOO | Hanunoo |
PANGO_SCRIPT_BUHID | Buhid |
PANGO_SCRIPT_TAGBANWA | Tagbanwa |
PANGO_SCRIPT_BRAILLE | Braille |
PANGO_SCRIPT_CYPRIOT | Cypriot |
PANGO_SCRIPT_LIMBU | Limbu |
PANGO_SCRIPT_OSMANYA | Osmanya |
PANGO_SCRIPT_SHAVIAN | Shavian |
PANGO_SCRIPT_LINEAR_B | Linear B |
PANGO_SCRIPT_TAI_LE | Tai Le |
PANGO_SCRIPT_UGARITIC | Ugaritic |
PANGO_SCRIPT_NEW_TAI_LUE | New Tai Lue. Since 1.10 |
PANGO_SCRIPT_BUGINESE | Buginese. Since 1.10 |
PANGO_SCRIPT_GLAGOLITIC | Glagolitic. Since 1.10 |
PANGO_SCRIPT_TIFINAGH | Tifinagh. Since 1.10 |
PANGO_SCRIPT_SYLOTI_NAGRI | Syloti Nagri. Since 1.10 |
PANGO_SCRIPT_OLD_PERSIAN | Old Persian. Since 1.10 |
PANGO_SCRIPT_KHAROSHTHI | Kharoshthi. Since 1.10 |
PANGO_SCRIPT_UNKNOWN | an unassigned code point. Since 1.14 |
PANGO_SCRIPT_BALINESE | Balinese. Since 1.14 |
PANGO_SCRIPT_CUNEIFORM | Cuneiform. Since 1.14 |
PANGO_SCRIPT_PHOENICIAN | Phoenician. Since 1.14 |
PANGO_SCRIPT_PHAGS_PA | Phags-pa. Since 1.14 |
PANGO_SCRIPT_NKO | N'Ko. Since 1.14 |
PANGO_SCRIPT_KAYAH_LI | Kayah Li. Since 1.20.1 |
PANGO_SCRIPT_LEPCHA | Lepcha. Since 1.20.1 |
PANGO_SCRIPT_REJANG | Rejang. Since 1.20.1 |
PANGO_SCRIPT_SUNDANESE | Sundanese. Since 1.20.1 |
PANGO_SCRIPT_SAURASHTRA | Saurashtra. Since 1.20.1 |
PANGO_SCRIPT_CHAM | Cham. Since 1.20.1 |
PANGO_SCRIPT_OL_CHIKI | Ol Chiki. Since 1.20.1 |
PANGO_SCRIPT_VAI | Vai. Since 1.20.1 |
PANGO_SCRIPT_CARIAN | Carian. Since 1.20.1 |
PANGO_SCRIPT_LYCIAN | Lycian. Since 1.20.1 |
PANGO_SCRIPT_LYDIAN | Lydian. Since 1.20.1 |
PANGO_SCRIPT_BATAK | Batak. Since 1.32 |
PANGO_SCRIPT_BRAHMI | Brahmi. Since 1.32 |
PANGO_SCRIPT_MANDAIC | Mandaic. Since 1.32 |
PANGO_SCRIPT_CHAKMA | Chakma. Since: 1.32 |
PANGO_SCRIPT_MEROITIC_CURSIVE | Meroitic Cursive. Since: 1.32 |
PANGO_SCRIPT_MEROITIC_HIEROGLYPHS | Meroitic Hieroglyphs. Since: 1.32 |
PANGO_SCRIPT_MIAO | Miao. Since: 1.32 |
PANGO_SCRIPT_SHARADA | Sharada. Since: 1.32 |
PANGO_SCRIPT_SORA_SOMPENG | Sora Sompeng. Since: 1.32 |
PANGO_SCRIPT_TAKRI | Takri. Since: 1.32 |

### PangoScriptIter

    typedef struct _PangoScriptIter PangoScriptIter;

A PangoScriptIter is used to iterate through a string and identify ranges in different scripts.

### PangoLanguage

    typedef struct _PangoLanguage PangoLanguage;

The PangoLanguage structure is used to represent a language.

PangoLanguage pointers can be efficiently copied and compared with each other.