* @title: Character Set Conversion
* @short_description: convert strings between different character sets
*
- * The g_convert() family of function wraps the functionality of iconv(). In
- * addition to pure character set conversions, GLib has functions to deal
- * with the extra complications of encodings for file names.
+ * The g_convert() family of function wraps the functionality of iconv().
+ * In addition to pure character set conversions, GLib has functions to
+ * deal with the extra complications of encodings for file names.
*
- * <refsect2 id="file-name-encodings">
- * <title>File Name Encodings</title>
- * <para>
- * Historically, Unix has not had a defined encoding for file
- * names: a file name is valid as long as it does not have path
- * separators in it ("/"). However, displaying file names may
- * require conversion: from the character set in which they were
- * created, to the character set in which the application
- * operates. Consider the Spanish file name
- * "<filename>Presentación.sxi</filename>". If the
- * application which created it uses ISO-8859-1 for its encoding,
- * </para>
- * <programlisting id="filename-iso8859-1">
+ * ## File Name Encodings
+ *
+ * Historically, UNIX has not had a defined encoding for file names:
+ * a file name is valid as long as it does not have path separators
+ * in it ("/"). However, displaying file names may require conversion:
+ * from the character set in which they were created, to the character
+ * set in which the application operates. Consider the Spanish file name
+ * "Presentación.sxi". If the application which created it uses
+ * ISO-8859-1 for its encoding,
+ * |[
* Character: P r e s e n t a c i ó n . s x i
* Hex code: 50 72 65 73 65 6e 74 61 63 69 f3 6e 2e 73 78 69
- * </programlisting>
- * <para>
+ * ]|
* However, if the application use UTF-8, the actual file name on
* disk would look like this:
- * </para>
- * <programlisting id="filename-utf-8">
+ * |[
* Character: P r e s e n t a c i ó n . s x i
* Hex code: 50 72 65 73 65 6e 74 61 63 69 c3 b3 6e 2e 73 78 69
- * </programlisting>
- * <para>
- * Glib uses UTF-8 for its strings, and GUI toolkits like GTK+
- * that use Glib do the same thing. If you get a file name from
- * the file system, for example, from readdir(3) or from g_dir_read_name(),
- * and you wish to display the file name to the user, you
- * <emphasis>will</emphasis> need to convert it into UTF-8. The
- * opposite case is when the user types the name of a file he
- * wishes to save: the toolkit will give you that string in
- * UTF-8 encoding, and you will need to convert it to the
- * character set used for file names before you can create the
- * file with open(2) or fopen(3).
- * </para>
- * <para>
+ * ]|
+ * Glib uses UTF-8 for its strings, and GUI toolkits like GTK+ that use
+ * Glib do the same thing. If you get a file name from the file system,
+ * for example, from readdir() or from g_dir_read_name(), and you wish
+ * to display the file name to the user, you will need to convert it
+ * into UTF-8. The opposite case is when the user types the name of a
+ * file he wishes to save: the toolkit will give you that string in
+ * UTF-8 encoding, and you will need to convert it to the character
+ * set used for file names before you can create the file with open()
+ * or fopen().
+ *
* By default, Glib assumes that file names on disk are in UTF-8
- * encoding. This is a valid assumption for file systems which
- * were created relatively recently: most applications use UTF-8
+ * encoding. This is a valid assumption for file systems which
+ * were created relatively recently: most applications use UTF-8
* encoding for their strings, and that is also what they use for
- * the file names they create. However, older file systems may
+ * the file names they create. However, older file systems may
* still contain file names created in "older" encodings, such as
- * ISO-8859-1. In this case, for compatibility reasons, you may
- * want to instruct Glib to use that particular encoding for file
- * names rather than UTF-8. You can do this by specifying the
- * encoding for file names in the <link
- * linkend="G_FILENAME_ENCODING"><envar>G_FILENAME_ENCODING</envar></link>
- * environment variable. For example, if your installation uses
- * ISO-8859-1 for file names, you can put this in your
- * <filename>~/.profile</filename>:
- * </para>
- * <programlisting>
+ * ISO-8859-1. In this case, for compatibility reasons, you may want
+ * to instruct Glib to use that particular encoding for file names
+ * rather than UTF-8. You can do this by specifying the encoding for
+ * file names in the [`G_FILENAME_ENCODING`][G_FILENAME_ENCODING]
+ * environment variable. For example, if your installation uses
+ * ISO-8859-1 for file names, you can put this in your `~/.profile`
+ * |[
* export G_FILENAME_ENCODING=ISO-8859-1
- * </programlisting>
- * <para>
+ * ]|
* Glib provides the functions g_filename_to_utf8() and
- * g_filename_from_utf8() to perform the necessary conversions. These
- * functions convert file names from the encoding specified in
- * <envar>G_FILENAME_ENCODING</envar> to UTF-8 and vice-versa.
- * <xref linkend="file-name-encodings-diagram"/> illustrates how
+ * g_filename_from_utf8() to perform the necessary conversions.
+ * These functions convert file names from the encoding specified
+ * in `G_FILENAME_ENCODING` to UTF-8 and vice-versa. This
+ * [diagram][file-name-encodings-diagram] illustrates how
* these functions are used to convert between UTF-8 and the
* encoding for file names in the file system.
- * </para>
- * <figure id="file-name-encodings-diagram">
- * <title>Conversion between File Name Encodings</title>
- * <graphic fileref="file-name-encodings.png" format="PNG"/>
- * </figure>
- * <refsect3 id="file-name-encodings-checklist">
- * <title>Checklist for Application Writers</title>
- * <para>
+ *
+ * ## Conversion between file name encodings # {#file-name-encodings-diagram)
+ *
+ * 
+ *
+ * ## Checklist for Application Writers
+ *
* This section is a practical summary of the detailed
- * description above. You can use this as a checklist of
+
* things to do to make sure your applications process file
* name encodings correctly.
- * </para>
- * <orderedlist>
- * <listitem><para>
- * If you get a file name from the file system from a function
- * such as readdir(3) or gtk_file_chooser_get_filename(),
- * you do not need to do any conversion to pass that
- * file name to functions like open(2), rename(2), or
- * fopen(3) — those are "raw" file names which the file
- * system understands.
- * </para></listitem>
- * <listitem><para>
- * If you need to display a file name, convert it to UTF-8 first by
- * using g_filename_to_utf8(). If conversion fails, display a string like
- * "<literal>Unknown file name</literal>". <emphasis>Do not</emphasis>
- * convert this string back into the encoding used for file names if you
- * wish to pass it to the file system; use the original file name instead.
- * For example, the document window of a word processor could display
- * "Unknown file name" in its title bar but still let the user save the
- * file, as it would keep the raw file name internally. This can happen
- * if the user has not set the <envar>G_FILENAME_ENCODING</envar>
- * environment variable even though he has files whose names are not
- * encoded in UTF-8.
- * </para></listitem>
- * <listitem><para>
- * If your user interface lets the user type a file name for saving or
- * renaming, convert it to the encoding used for file names in the file
- * system by using g_filename_from_utf8(). Pass the converted file name
- * to functions like fopen(3). If conversion fails, ask the user to enter
- * a different file name. This can happen if the user types Japanese
- * characters when <envar>G_FILENAME_ENCODING</envar> is set to
- * <literal>ISO-8859-1</literal>, for example.
- * </para></listitem>
- * </orderedlist>
- * </refsect3>
- * </refsect2>
+ *
+ * 1. If you get a file name from the file system from a function
+ * such as readdir() or gtk_file_chooser_get_filename(), you do
+ * not need to do any conversion to pass that file name to
+ * functions like open(), rename(), or fopen() -- those are "raw"
+ * file names which the file system understands.
+ *
+ * 2. If you need to display a file name, convert it to UTF-8 first
+ * by using g_filename_to_utf8(). If conversion fails, display a
+ * string like "Unknown file name". Do not convert this string back
+ * into the encoding used for file names if you wish to pass it to
+ * the file system; use the original file name instead.
+ *
+ * For example, the document window of a word processor could display
+ * "Unknown file name" in its title bar but still let the user save
+ * the file, as it would keep the raw file name internally. This
+ * can happen if the user has not set the `G_FILENAME_ENCODING`
+ * environment variable even though he has files whose names are
+ * not encoded in UTF-8.
+ *
+ * 3. If your user interface lets the user type a file name for saving
+ * or renaming, convert it to the encoding used for file names in
+ * the file system by using g_filename_from_utf8(). Pass the converted
+ * file name to functions like fopen(). If conversion fails, ask the
+ * user to enter a different file name. This can happen if the user
+ * types Japanese characters when `G_FILENAME_ENCODING` is set to
+ * `ISO-8859-1`, for example.
*/
/* We try to terminate strings in unknown charsets with this many zero bytes
* GLib provides g_convert() and g_locale_to_utf8() which are likely
* more convenient than the raw iconv wrappers.
*
- * Return value: a "conversion descriptor", or (GIConv)-1 if
+ * Returns: a "conversion descriptor", or (GIConv)-1 if
* opening the converter failed.
**/
GIConv
* GLib provides g_convert() and g_locale_to_utf8() which are likely
* more convenient than the raw iconv wrappers.
*
- * Return value: count of non-reversible conversions, or -1 on error
+ * Returns: count of non-reversible conversions, or -1 on error
**/
gsize
g_iconv (GIConv converter,
* GLib provides g_convert() and g_locale_to_utf8() which are likely
* more convenient than the raw iconv wrappers.
*
- * Return value: -1 on error, 0 on success
+ * Returns: -1 on error, 0 on success
**/
gint
g_iconv_close (GIConv converter)
/**
* g_convert_with_iconv:
* @str: the string to convert
- * @len: the length of the string, or -1 if the string is
- * nul-terminated<footnoteref linkend="nul-unsafe"/>.
+ * @len: the length of the string in bytes, or -1 if the string is
+ * nul-terminated (Note that some encodings may allow nul
+ * bytes to occur inside strings. In that case, using -1
+ * for the @len parameter is unsafe)
* @converter: conversion descriptor from g_iconv_open()
* @bytes_read: location to store the number of bytes in the
* input string that were successfully converted, or %NULL.
*
* Converts a string from one character set to another.
*
- * Note that you should use g_iconv() for streaming
- * conversions<footnote id="streaming-state">
- * <para>
+ * Note that you should use g_iconv() for streaming conversions.
* Despite the fact that @byes_read can return information about partial
- * characters, the <literal>g_convert_...</literal> functions
- * are not generally suitable for streaming. If the underlying converter
- * being used maintains internal state, then this won't be preserved
- * across successive calls to g_convert(), g_convert_with_iconv() or
- * g_convert_with_fallback(). (An example of this is the GNU C converter
- * for CP1255 which does not emit a base character until it knows that
- * the next character is not a mark that could combine with the base
- * character.)
- * </para>
- * </footnote>.
+ * characters, the g_convert_... functions are not generally suitable
+ * for streaming. If the underlying converter maintains internal state,
+ * then this won't be preserved across successive calls to g_convert(),
+ * g_convert_with_iconv() or g_convert_with_fallback(). (An example of
+ * this is the GNU C converter for CP1255 which does not emit a base
+ * character until it knows that the next character is not a mark that
+ * could combine with the base character.)
*
- * Return value: If the conversion was successful, a newly allocated
+ * Returns: If the conversion was successful, a newly allocated
* nul-terminated string, which must be freed with
* g_free(). Otherwise %NULL and @error will be set.
**/
/**
* g_convert:
* @str: the string to convert
- * @len: the length of the string, or -1 if the string is
- * nul-terminated<footnote id="nul-unsafe">
- <para>
- Note that some encodings may allow nul bytes to
- occur inside strings. In that case, using -1 for
- the @len parameter is unsafe.
- </para>
- </footnote>.
+ * @len: the length of the string in bytes, or -1 if the string is
+ * nul-terminated (Note that some encodings may allow nul
+ * bytes to occur inside strings. In that case, using -1
+ * for the @len parameter is unsafe)
* @to_codeset: name of character set into which to convert @str
* @from_codeset: character set of @str.
* @bytes_read: (out): location to store the number of bytes in the
*
* Converts a string from one character set to another.
*
- * Note that you should use g_iconv() for streaming
- * conversions<footnoteref linkend="streaming-state"/>.
+ * Note that you should use g_iconv() for streaming conversions.
+ * Despite the fact that @byes_read can return information about partial
+ * characters, the g_convert_... functions are not generally suitable
+ * for streaming. If the underlying converter maintains internal state,
+ * then this won't be preserved across successive calls to g_convert(),
+ * g_convert_with_iconv() or g_convert_with_fallback(). (An example of
+ * this is the GNU C converter for CP1255 which does not emit a base
+ * character until it knows that the next character is not a mark that
+ * could combine with the base character.)
+ *
+ * Using extensions such as "//TRANSLIT" may not work (or may not work
+ * well) on many platforms. Consider using g_str_to_ascii() instead.
*
- * Return value: If the conversion was successful, a newly allocated
+ * Returns: If the conversion was successful, a newly allocated
* nul-terminated string, which must be freed with
* g_free(). Otherwise %NULL and @error will be set.
**/
/**
* g_convert_with_fallback:
* @str: the string to convert
- * @len: the length of the string, or -1 if the string is
- * nul-terminated<footnoteref linkend="nul-unsafe"/>.
+ * @len: the length of the string in bytes, or -1 if the string is
+ * nul-terminated (Note that some encodings may allow nul
+ * bytes to occur inside strings. In that case, using -1
+ * for the @len parameter is unsafe)
* @to_codeset: name of character set into which to convert @str
* @from_codeset: character set of @str.
* @fallback: UTF-8 string to use in place of character not
* to @to_codeset in their iconv() functions,
* in which case GLib will simply return that approximate conversion.
*
- * Note that you should use g_iconv() for streaming
- * conversions<footnoteref linkend="streaming-state"/>.
+ * Note that you should use g_iconv() for streaming conversions.
+ * Despite the fact that @byes_read can return information about partial
+ * characters, the g_convert_... functions are not generally suitable
+ * for streaming. If the underlying converter maintains internal state,
+ * then this won't be preserved across successive calls to g_convert(),
+ * g_convert_with_iconv() or g_convert_with_fallback(). (An example of
+ * this is the GNU C converter for CP1255 which does not emit a base
+ * character until it knows that the next character is not a mark that
+ * could combine with the base character.)
*
- * Return value: If the conversion was successful, a newly allocated
+ * Returns: If the conversion was successful, a newly allocated
* nul-terminated string, which must be freed with
* g_free(). Otherwise %NULL and @error will be set.
**/
* @opsysstring: a string in the encoding of the current locale. On Windows
* this means the system codepage.
* @len: the length of the string, or -1 if the string is
- * nul-terminated<footnoteref linkend="nul-unsafe"/>.
+ * nul-terminated (Note that some encodings may allow nul
+ * bytes to occur inside strings. In that case, using -1
+ * for the @len parameter is unsafe)
* @bytes_read: location to store the number of bytes in the
* input string that were successfully converted, or %NULL.
* Even if the conversion was successful, this may be
*
* Converts a string which is in the encoding used for strings by
* the C runtime (usually the same as that used by the operating
- * system) in the <link linkend="setlocale">current locale</link> into a
- * UTF-8 string.
+ * system) in the [current locale][setlocale] into a UTF-8 string.
*
- * Return value: A newly-allocated buffer containing the converted string,
+ * Returns: A newly-allocated buffer containing the converted string,
* or %NULL on an error, and error will be set.
**/
gchar *
* g_locale_from_utf8:
* @utf8string: a UTF-8 encoded string
* @len: the length of the string, or -1 if the string is
- * nul-terminated<footnoteref linkend="nul-unsafe"/>.
+ * nul-terminated (Note that some encodings may allow nul
+ * bytes to occur inside strings. In that case, using -1
+ * for the @len parameter is unsafe)
* @bytes_read: location to store the number of bytes in the
* input string that were successfully converted, or %NULL.
* Even if the conversion was successful, this may be
*
* Converts a string from UTF-8 to the encoding used for strings by
* the C runtime (usually the same as that used by the operating
- * system) in the <link linkend="setlocale">current locale</link>. On
- * Windows this means the system codepage.
+ * system) in the [current locale][setlocale]. On Windows this means
+ * the system codepage.
*
- * Return value: A newly-allocated buffer containing the converted string,
+ * Returns: A newly-allocated buffer containing the converted string,
* or %NULL on an error, and error will be set.
**/
gchar *
* representation of a filename, see g_filename_display_name().
*
* On Unix, the character sets are determined by consulting the
- * environment variables <envar>G_FILENAME_ENCODING</envar> and
- * <envar>G_BROKEN_FILENAMES</envar>. On Windows, the character set
- * used in the GLib API is always UTF-8 and said environment variables
- * have no effect.
+ * environment variables `G_FILENAME_ENCODING` and `G_BROKEN_FILENAMES`.
+ * On Windows, the character set used in the GLib API is always UTF-8
+ * and said environment variables have no effect.
*
- * <envar>G_FILENAME_ENCODING</envar> may be set to a comma-separated list
- * of character set names. The special token "@locale" is taken to
- * mean the character set for the <link linkend="setlocale">current
- * locale</link>. If <envar>G_FILENAME_ENCODING</envar> is not set, but
- * <envar>G_BROKEN_FILENAMES</envar> is, the character set of the current
- * locale is taken as the filename encoding. If neither environment variable
- * is set, UTF-8 is taken as the filename encoding, but the character
- * set of the current locale is also put in the list of encodings.
+ * `G_FILENAME_ENCODING` may be set to a comma-separated list of
+ * character set names. The special token "@locale" is taken
+ * to mean the character set for the [current locale][setlocale].
+ * If `G_FILENAME_ENCODING` is not set, but `G_BROKEN_FILENAMES` is,
+ * the character set of the current locale is taken as the filename
+ * encoding. If neither environment variable is set, UTF-8 is taken
+ * as the filename encoding, but the character set of the current locale
+ * is also put in the list of encodings.
*
* The returned @charsets belong to GLib and must not be freed.
*
* Note that on Unix, regardless of the locale character set or
- * <envar>G_FILENAME_ENCODING</envar> value, the actual file names present
+ * `G_FILENAME_ENCODING` value, the actual file names present
* on a system might be in any random encoding or just gibberish.
*
- * Return value: %TRUE if the filename encoding is UTF-8.
+ * Returns: %TRUE if the filename encoding is UTF-8.
*
* Since: 2.6
*/
* g_filename_to_utf8:
* @opsysstring: a string in the encoding for filenames
* @len: the length of the string, or -1 if the string is
- * nul-terminated<footnoteref linkend="nul-unsafe"/>.
+ * nul-terminated (Note that some encodings may allow nul
+ * bytes to occur inside strings. In that case, using -1
+ * for the @len parameter is unsafe)
* @bytes_read: location to store the number of bytes in the
* input string that were successfully converted, or %NULL.
* Even if the conversion was successful, this may be
* Converts a string which is in the encoding used by GLib for
* filenames into a UTF-8 string. Note that on Windows GLib uses UTF-8
* for filenames; on other platforms, this function indirectly depends on
- * the <link linkend="setlocale">current locale</link>.
+ * the [current locale][setlocale].
*
- * Return value: The converted string, or %NULL on an error.
+ * Returns: The converted string, or %NULL on an error.
**/
gchar*
g_filename_to_utf8 (const gchar *opsysstring,
* Converts a string from UTF-8 to the encoding GLib uses for
* filenames. Note that on Windows GLib uses UTF-8 for filenames;
* on other platforms, this function indirectly depends on the
- * <link linkend="setlocale">current locale</link>.
+ * [current locale][setlocale].
*
- * Return value: (array length=bytes_written) (element-type guint8) (transfer full):
+ * Returns: (array length=bytes_written) (element-type guint8) (transfer full):
* The converted string, or %NULL on an error.
**/
gchar*
* Converts an escaped ASCII-encoded URI to a local filename in the
* encoding used for filenames.
*
- * Return value: (type filename): a newly-allocated string holding
+ * Returns: (type filename): a newly-allocated string holding
* the resulting filename, or %NULL on an error.
**/
gchar *
* Converts an absolute filename to an escaped ASCII-encoded URI, with the path
* component following Section 3.3. of RFC 2396.
*
- * Return value: a newly-allocated string holding the resulting
+ * Returns: a newly-allocated string holding the resulting
* URI, or %NULL on an error.
**/
gchar *
* This function is preferred over g_filename_display_name() if you know the
* whole path, as it allows translation.
*
- * Return value: a newly allocated string containing
+ * Returns: a newly allocated string containing
* a rendition of the basename of the filename in valid UTF-8
*
* Since: 2.6
* g_filename_display_basename(), since that allows location-based
* translation of filenames.
*
- * Return value: a newly allocated string containing
+ * Returns: a newly allocated string containing
* a rendition of the filename in valid UTF-8
*
* Since: 2.6
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