KeyFile
GKeyFile parses .ini-like config files.
GKeyFile lets you parse, edit or create files containing groups of key-value pairs, which we call "key files" for lack of a better name. Several freedesktop.org specifications use key files now, e.g the Desktop Entry Specification and the Icon Theme Specification.
The syntax of key files is described in detail in the Desktop Entry Specification, here is a quick summary: Key files consists of groups of key-value pairs, interspersed with comments.
# this is just an example
# there can be comments before the first group
[First Group]
Name=Key File Example\tthis value shows\nescaping
# localized strings are stored in multiple key-value pairs
Welcome=Hello
Welcome[de]=Hallo
Welcome[fr_FR]=Bonjour
Welcome[it]=Ciao
[Another Group]
Numbers=2;20;-200;0
Booleans=true;false;true;trueLines beginning with a '#' and blank lines are considered comments.
Groups are started by a header line containing the group name enclosed in '' and '', and ended implicitly by the start of the next group or the end of the file. Each key-value pair must be contained in a group.
Key-value pairs generally have the form key=value, with the exception of localized strings, which have the form key[locale]=value, with a locale identifier of the form lang_COUNTRY@MODIFIER where COUNTRY and MODIFIER are optional. Space before and after the '=' character are ignored. Newline, tab, carriage return and backslash characters in value are escaped as \n, \t, \r, and \\\\, respectively. To preserve leading spaces in values, these can also be escaped as \s.
Key files can store strings (possibly with localized variants), integers, booleans and lists of these. Lists are separated by a separator character, typically ';' or ','. To use the list separator character in a value in a list, it has to be escaped by prefixing it with a backslash.
This syntax is obviously inspired by the .ini files commonly met on Windows, but there are some important differences:
.ini files use the ';' character to begin comments, key files use the '#' character.
Key files do not allow for ungrouped keys meaning only comments can precede the first group.
Key files are always encoded in UTF-8.
Key and Group names are case-sensitive. For example, a group called GROUP is a different from group.
.ini files don't have a strongly typed boolean entry type, they only have GetProfileInt(). In key files, only true and false (in lower case) are allowed.
Note that in contrast to the Desktop Entry Specification, groups in key files may contain the same key multiple times; the last entry wins. Key files may also contain multiple groups with the same name; they are merged together. Another difference is that keys and group names in key files are not restricted to ASCII characters.
Here is an example of loading a key file and reading a value:
g_autoptr(GError) error = NULL;
g_autoptr(GKeyFile) key_file = g_key_file_new ();
if (!g_key_file_load_from_file (key_file, "key-file.ini", flags, &error))
{
if (!g_error_matches (error, G_FILE_ERROR, G_FILE_ERROR_NOENT))
g_warning ("Error loading key file: %s", error->message);
return;
}
g_autofree gchar *val = g_key_file_get_string (key_file, "Group Name", "SomeKey", &error);
if (val == NULL &&
!g_error_matches (error, G_KEY_FILE_ERROR, G_KEY_FILE_ERROR_KEY_NOT_FOUND))
{
g_warning ("Error finding key in key file: %s", error->message);
return;
}
else if (val == NULL)
{
// Fall back to a default value.
val = g_strdup ("default-value");
}Here is an example of creating and saving a key file:
g_autoptr(GKeyFile) key_file = g_key_file_new ();
const gchar *val = …;
g_autoptr(GError) error = NULL;
g_key_file_set_string (key_file, "Group Name", "SomeKey", val);
// Save as a file.
if (!g_key_file_save_to_file (key_file, "key-file.ini", &error))
{
g_warning ("Error saving key file: %s", error->message);
return;
}
// Or store to a GBytes for use elsewhere.
gsize data_len;
g_autofree guint8 *data = (guint8 *) g_key_file_to_data (key_file, &data_len, &error);
if (data == NULL)
{
g_warning ("Error saving key file: %s", error->message);
return;
}
g_autoptr(GBytes) bytes = g_bytes_new_take (g_steal_pointer (&data), data_len);Skipped during bindings generation
parameter
length: length: Out parameter is not supportedparameter
length: length: Out parameter is not supportedparameter
length: length: Out parameter is not supportedparameter
length: length: Out parameter is not supportedparameter
length: length: Out parameter is not supportedparameter
length: length: Out parameter is not supportedparameter
length: length: Out parameter is not supportedparameter
full_path: full_path: Out parameter is not supportedparameter
full_path: full_path: Out parameter is not supportedparameter
list: Array parameter of type gboolean is not supportedparameter
list: Array parameter of type gdouble is not supportedparameter
list: Array parameter of type gint is not supportedparameter
length: length: Out parameter is not supported
Constructors
Functions
Returns the value associated with @key under @group_name as a boolean.
Retrieves a comment above @key from @group_name. If @key is null then @comment will be read from above
Returns the value associated with @key under @group_name as an integer.
Returns the actual locale which the result of g_key_file_get_locale_string() or g_key_file_get_locale_string_list() came from.
Returns the value associated with @key under @group_name translated in the given @locale if available. If @locale is null then the current locale is assumed.
Returns the name of the start group of the file.
Loads a key file from the data in @bytes into an empty #GKeyFile structure. If the object cannot be created then %error is set to a #GKeyFileError.
Loads a key file from memory into an empty #GKeyFile structure. If the object cannot be created then %error is set to a #GKeyFileError.
Loads a key file into an empty #GKeyFile structure.
Removes a comment above @key from @group_name. If @key is null then @comment will be removed above @group_name. If both @key and @group_name are null, then @comment will be removed above the first group in the file.
Removes the specified group, @group_name, from the key file.
Writes the contents of @key_file to @filename using g_file_set_contents(). If you need stricter guarantees about durability of the written file than are provided by g_file_set_contents(), use g_file_set_contents_full() with the return value of g_key_file_to_data().
Associates a new boolean value with @key under @group_name. If @key cannot be found then it is created.
Places a comment above @key from @group_name.
Associates a new integer value with @key under @group_name. If @key cannot be found then it is created.
Sets the character which is used to separate values in lists. Typically ';' or ',' are used as separators. The default list separator is ';'.
Associates a string value for @key and @locale under @group_name. If the translation for @key cannot be found then it is created.
Associates a new string value with @key under @group_name. If @key cannot be found then it is created. If @group_name cannot be found then it is created. Unlike g_key_file_set_value(), this function handles characters that need escaping, such as newlines.
Associates a list of string values for @key under @group_name. If @key cannot be found then it is created. If @group_name cannot be found then it is created.