GConf Core Interfaces

GConf Core Interfaces — Basic functions to initialize GConf and get/set values

Synopsis




gboolean    gconf_init                      (int argc,
                                             char **argv,
                                             GError **err);
void        gconf_preinit                   (gpointer app,
                                             gpointer mod_info);
void        gconf_postinit                  (gpointer app,
                                             gpointer mod_info);
gboolean    gconf_is_initialized            (void);
void        (*GConfNotifyFunc)              (GConfEngine *conf,
                                             guint cnxn_id,
                                             GConfEntry *entry,
                                             gpointer user_data);
guint       gconf_engine_notify_add         (GConfEngine *conf,
                                             const gchar *namespace_section,
                                             GConfNotifyFunc func,
                                             gpointer user_data,
                                             GError **err);
void        gconf_engine_notify_remove      (GConfEngine *conf,
                                             guint cnxn);
GConfValue* gconf_engine_get                (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);
GConfValue* gconf_engine_get_without_default
                                            (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);
GConfEntry* gconf_engine_get_entry          (GConfEngine *conf,
                                             const gchar *key,
                                             const gchar *locale,
                                             gboolean use_schema_default,
                                             GError **err);
GConfValue* gconf_engine_get_with_locale    (GConfEngine *conf,
                                             const gchar *key,
                                             const gchar *locale,
                                             GError **err);
GConfValue* gconf_engine_get_default_from_schema
                                            (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);
gboolean    gconf_engine_set                (GConfEngine *conf,
                                             const gchar *key,
                                             const GConfValue *value,
                                             GError **err);
gboolean    gconf_engine_unset              (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);
gboolean    gconf_engine_associate_schema   (GConfEngine *conf,
                                             const gchar *key,
                                             const gchar *schema_key,
                                             GError **err);
GSList*     gconf_engine_all_entries        (GConfEngine *conf,
                                             const gchar *dir,
                                             GError **err);
GSList*     gconf_engine_all_dirs           (GConfEngine *conf,
                                             const gchar *dir,
                                             GError **err);
void        gconf_engine_suggest_sync       (GConfEngine *conf,
                                             GError **err);
gboolean    gconf_engine_dir_exists         (GConfEngine *conf,
                                             const gchar *dir,
                                             GError **err);
void        gconf_engine_remove_dir         (GConfEngine *conf,
                                             const gchar *dir,
                                             GError **err);
gboolean    gconf_engine_key_is_writable    (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);
gboolean    gconf_valid_key                 (const gchar *key,
                                             gchar **why_invalid);
gboolean    gconf_key_is_below              (const gchar *above,
                                             const gchar *below);
gchar*      gconf_concat_dir_and_key        (const gchar *dir,
                                             const gchar *key);
gchar*      gconf_unique_key                (void);
char*       gconf_escape_key                (const char *arbitrary_text,
                                             int len);
char*       gconf_unescape_key              (const char *escaped_key,
                                             int len);
gdouble     gconf_engine_get_float          (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);
gint        gconf_engine_get_int            (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);
gchar*      gconf_engine_get_string         (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);
gboolean    gconf_engine_get_bool           (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);
GConfSchema* gconf_engine_get_schema        (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);
GSList*     gconf_engine_get_list           (GConfEngine *conf,
                                             const gchar *key,
                                             GConfValueType list_type,
                                             GError **err);
gboolean    gconf_engine_get_pair           (GConfEngine *conf,
                                             const gchar *key,
                                             GConfValueType car_type,
                                             GConfValueType cdr_type,
                                             gpointer car_retloc,
                                             gpointer cdr_retloc,
                                             GError **err);
gboolean    gconf_engine_set_float          (GConfEngine *conf,
                                             const gchar *key,
                                             gdouble val,
                                             GError **err);
gboolean    gconf_engine_set_int            (GConfEngine *conf,
                                             const gchar *key,
                                             gint val,
                                             GError **err);
gboolean    gconf_engine_set_string         (GConfEngine *conf,
                                             const gchar *key,
                                             const gchar *val,
                                             GError **err);
gboolean    gconf_engine_set_bool           (GConfEngine *conf,
                                             const gchar *key,
                                             gboolean val,
                                             GError **err);
gboolean    gconf_engine_set_schema         (GConfEngine *conf,
                                             const gchar *key,
                                             const GConfSchema *val,
                                             GError **err);
gboolean    gconf_engine_set_list           (GConfEngine *conf,
                                             const gchar *key,
                                             GConfValueType list_type,
                                             GSList *list,
                                             GError **err);
gboolean    gconf_engine_set_pair           (GConfEngine *conf,
                                             const gchar *key,
                                             GConfValueType car_type,
                                             GConfValueType cdr_type,
                                             gconstpointer address_of_car,
                                             gconstpointer address_of_cdr,
                                             GError **err);
            GConfEnumStringPair;
gboolean    gconf_string_to_enum            (GConfEnumStringPair lookup_table[],
                                             const gchar *str,
                                             gint *enum_value_retloc);
const gchar* gconf_enum_to_string           (GConfEnumStringPair lookup_table[],
                                             gint enum_value);
void        gconf_clear_cache               (GConfEngine *conf,
                                             GError **err);
void        gconf_synchronous_sync          (GConfEngine *conf,
                                             GError **err);
GConfValue* gconf_engine_get_full           (GConfEngine *conf,
                                             const gchar *key,
                                             const gchar *locale,
                                             gboolean use_schema_default,
                                             gboolean *is_default_p,
                                             gboolean *is_writable_p,
                                             GError **err);

Description

These functions initialize GConf, and communicate with the gconfd server via a GConfEngine object. You can install a notification request on the server, get values, set values, list directories, and associate schema names with keys.

Most of this interface is replicated in the GObject wrapper (GConfClient object); an alternative to the value-setting functions is the GConfChangeSet interface.

Details

gconf_init ()

gboolean    gconf_init                      (int argc,
                                             char **argv,
                                             GError **err);

Warning

gconf_init is deprecated and should not be used in newly-written code.

Initializes the GConf library. Creates a connection to a CORBA ORB, and initializes OAF (the object activation framework) if it isn't already initialized.

argc :
argv :
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE otherwise.

gconf_preinit ()

void        gconf_preinit                   (gpointer app,
                                             gpointer mod_info);

Warning

gconf_preinit is deprecated and should not be used in newly-written code.

app :
mod_info :

gconf_postinit ()

void        gconf_postinit                  (gpointer app,
                                             gpointer mod_info);

Warning

gconf_postinit is deprecated and should not be used in newly-written code.

app :
mod_info :

gconf_is_initialized ()

gboolean    gconf_is_initialized            (void);

Warning

gconf_is_initialized is deprecated and should not be used in newly-written code.

Asks whether the library has been initialized.

Returns : TRUE if the library has been initialized.

GConfNotifyFunc ()

void        (*GConfNotifyFunc)              (GConfEngine *conf,
                                             guint cnxn_id,
                                             GConfEntry *entry,
                                             gpointer user_data);

A callback function invoked when a key's value changes. The cnxn_id parameter will be the connection ID returned from gconf_engine_notify_add(). key will be the full path of the changed key, value will be the new value if the key is set. If the key is unset, value will be the default value if one exists, or NULL otherwise. is_default indicates whether a value is a default setting or a user setting. If value is NULL, is_default will be TRUE. user_data is the data passed to gconf_engine_notify_add().

conf : the GConfEngine passed to gconf_engine_notify_add().
cnxn_id : the ID returned from gconf_engine_notify_add().
entry :
user_data : the user data passed to gconf_engine_notify_add().

gconf_engine_notify_add ()

guint       gconf_engine_notify_add         (GConfEngine *conf,
                                             const gchar *namespace_section,
                                             GConfNotifyFunc func,
                                             gpointer user_data,
                                             GError **err);

Registers a notification request with the gconfd server. The server will notify the client when any key at or below namespace_section is set or unset. Try to watch the smallest possible part of the namespace; otherwise you will slow down the server and your application with unnecessary notifications. Note that you should prefer gconf_client_notify_add() if you're using the GObject wrapper library, because gconf_client_notify_add() does not require a client-server conversation for every callback. gconf_engine_notify_add() requests a different server notification for every callback. The function returns an ID you can use to remove the notification request; 0 is an invalid ID, and is returned if an error occurs.

conf : a GConfEngine to monitor for changes.
namespace_section : the directory or key to watch; you will be notified of changes at or below this point.
func : the callback to invoke when a notification is received from the server.
user_data : the data to pass to the callback.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : an ID for the notification request, or 0 on error.

gconf_engine_notify_remove ()

void        gconf_engine_notify_remove      (GConfEngine *conf,
                                             guint cnxn);

Removes a notification request.

conf : the GConfEngine you were monitoring for changes.
cnxn : The ID returned by gconf_engine_notify_add().

gconf_engine_get ()

GConfValue* gconf_engine_get                (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);

Returns the GConfValue stored at key, or NULL if no value is set. You must call gconf_value_free() to free the returned value. If you know the expected type of the value, you probably want to use the type-specific convenience wrappers (gconf_engine_get_int(), etc.) because they will do the type-checking for you and return the appropriate type. Automatically returns the default value for a key, if the key is unset and a default exists.

conf : a GConfEngine to get the value from.
key : the key to get.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : newly-allocated GConfValue, or NULL if unset and no default exists.

gconf_engine_get_without_default ()

GConfValue* gconf_engine_get_without_default
                                            (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);

Identical to gconf_engine_get(), except that it will return NULL in place of the default value if the key is unset. Note that gconf_engine_get() can also return NULL if no default exists or an error occurs.

conf : a GConfEngine to get the value from.
key : the key to get.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : newly-allocated GConfValue, or NULL if unset.

gconf_engine_get_entry ()

GConfEntry* gconf_engine_get_entry          (GConfEngine *conf,
                                             const gchar *key,
                                             const gchar *locale,
                                             gboolean use_schema_default,
                                             GError **err);

Obtain the full GConfEntry for a value.

conf : a GConfEngine.
key : the key to get.
locale : preferred locale (as in the locale-related environment variables).
use_schema_default : a gboolean value indicating whether the default value associated with schema should be used.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : a GConfEntry.

gconf_engine_get_with_locale ()

GConfValue* gconf_engine_get_with_locale    (GConfEngine *conf,
                                             const gchar *key,
                                             const gchar *locale,
                                             GError **err);

Requests the value appropriate for a particular locale. Right now, only values of type GCONF_VALUE_SCHEMA are localized; the locale is meaningless for other value types. Also, gconf_engine_get() automatically requests the value in the user's current locale. So this function is only useful if you want a schema for some locale other than the user's current locale. Except for the additional argument, this function is identical to gconf_engine_get() in all respects.

conf : a GConfEngine to get the value from.
key : the key to get.
locale : preferred locale (as in the locale-related environment variables).
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : newly-allocated GConfValue, or NULL if unset.

gconf_engine_get_default_from_schema ()

GConfValue* gconf_engine_get_default_from_schema
                                            (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);

Returns the default value stored in the key's schema, if the key has a schema associated and the schema exists and the schema contains a default value. Note that gconf_engine_get(), gconf_engine_get_string(), and so on already return the default value if no other value is found, so normally you do not need this function. This function is just for convenience; you could also get the GConfMetaInfo for the key, read the schema name from there, then look up the schema by name and extract the default value.

conf : a GConfEngine to get the value from.
key : the key to get the default value for.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : newly-allocated GConfValue, or NULL if unset.

gconf_engine_set ()

gboolean    gconf_engine_set                (GConfEngine *conf,
                                             const gchar *key,
                                             const GConfValue *value,
                                             GError **err);

Sets the value of key to value. Does not modify the passed-in GConfValue, you must free it yourself. You may prefer a type-specific convenience wrapper, such as gconf_engine_set_int().

An error of note is GCONF_OVERRIDDEN, indicating that the system administrator has "forced" a value for this key. If no writable configuration sources exist, it is not an error, but GConf will just forget all your values; this allows users to have a configuration-free setup without a constant barrage of error messages.

conf : a GConfEngine to set the value in.
key : the key to set.
value : the new value of key.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE on error.

gconf_engine_unset ()

gboolean    gconf_engine_unset              (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);

Unsets the value of key; if key is already unset, has no effect. An error of note is GCONF_OVERRIDDEN, indicating that the system administrator has "forced" a value for this key.

conf : a GConfEngine to affect.
key : the key to unset.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE on error.

gconf_engine_associate_schema ()

gboolean    gconf_engine_associate_schema   (GConfEngine *conf,
                                             const gchar *key,
                                             const gchar *schema_key,
                                             GError **err);

Directs GConf to find the schema for key at location schema_key. That is, the value stored at schema_key should have type GCONF_VALUE_SCHEMA, and be descriptive of key. Normally you don't call this function from C code; you can ship a special file with your application and ask gconftool to install schema associations into the database during "make install."

conf : a GConfEngine to affect.
key : the key to associate the schema with.
schema_key : the key where the schema will be stored.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE on error.

gconf_engine_all_entries ()

GSList*     gconf_engine_all_entries        (GConfEngine *conf,
                                             const gchar *dir,
                                             GError **err);

Lists the key-value pairs in dir. Does not list subdirectories; for that use gconf_engine_all_dirs(). The returned list contains GConfEntry objects. A GConfEntry contains an absolute key and a value. The list is not recursive, it contains only the immediate children of dir. To free the returned list, gconf_entry_free() each list element, then g_slist_free() the list itself.

conf : a GConfEngine.
dir : Directory to list.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : List of GConfEntry.

gconf_engine_all_dirs ()

GSList*     gconf_engine_all_dirs           (GConfEngine *conf,
                                             const gchar *dir,
                                             GError **err);

Lists the subdirectories in dir. The returned list contains allocated strings. Each string is the absolute path of a subdirectory. You should g_free() each string in the list, then g_slist_free() the list itself.

conf : a GConfEngine.
dir : Directory to get subdirectories from.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : List of allocated subdirectory names.

gconf_engine_suggest_sync ()

void        gconf_engine_suggest_sync       (GConfEngine *conf,
                                             GError **err);

Suggests to gconfd that you've just finished a block of changes, and it would be an optimal time to sync to permanent storage. This is only a suggestion; and gconfd will eventually sync even if you don't call gconf_engine_suggest_sync(). This function is just a "hint" provided to gconfd to maximize efficiency and minimize data loss.

conf : the GConfEngine to suggest syncing to.
err : the return location for an allocated GError, or NULL to ignore errors.

gconf_engine_dir_exists ()

gboolean    gconf_engine_dir_exists         (GConfEngine *conf,
                                             const gchar *dir,
                                             GError **err);

Queries whether the directory dir exists in the GConf database. Returns TRUE or FALSE.

conf : a GConfEngine.
dir : Directory to check for.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE or FALSE.

gconf_engine_remove_dir ()

void        gconf_engine_remove_dir         (GConfEngine *conf,
                                             const gchar *dir,
                                             GError **err);

This function first checks the validity of the gconf key. In case of a local GConfEngine it removes the directory from the source backend calling gconf_sources_remove_dir(). Otherwise it obtains the configuration database using gconf_engine_get_database() and removes the directory from the database calling ConfigDatabase_remove_dir().

conf : a GConfEngine.
dir : the name of the directory to be removed.
err : the return location for an allocated GError, or NULL to ignore errors.

gconf_engine_key_is_writable ()

gboolean    gconf_engine_key_is_writable    (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);

Checks whether the key is writable.

conf : a GConfEngine.
key : the value to be changed.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE if the key is writable, FALSE if the key is read only.

gconf_valid_key ()

gboolean    gconf_valid_key                 (const gchar *key,
                                             gchar **why_invalid);

Asks whether a key is syntactically correct, that is, it ensures that the key consists of slash-separated strings and contains only legal characters. Normally you shouldn't need to call this function; the GConf functions all check this for you and return an error if the key is invalid. However, it may be useful to validate input to an entry field or the like. If you pass a non-NULL address as the why_invalid argument, an allocated string is returned explaining why the key is invalid, if it is. If the key is valid the why_invalid argument is unused.

key : key to check.
why_invalid : return location for an explanation of the problem, if any. g_free() the returned string.
Returns : TRUE if the key is valid, or FALSE if not.

gconf_key_is_below ()

gboolean    gconf_key_is_below              (const gchar *above,
                                             const gchar *below);

Asks whether the key below would be found below the key above, were they both to exist in the database. For example, /foo is always found below / and above /foo/bar. This probably isn't useful but GConf uses it internally so here it is if you need it.

above : the key on the "left hand side" of the predicate.
below : the key on the "right hand side."
Returns : TRUE or FALSE.

gconf_concat_dir_and_key ()

gchar*      gconf_concat_dir_and_key        (const gchar *dir,
                                             const gchar *key);

Concatenates the dir and key passed removing the unnecessary '/' characters and returns the new string.

dir : the directory.
key : the key.
Returns : the newly concatenated string.

gconf_unique_key ()

gchar*      gconf_unique_key                (void);

Generates a new and unique key using serial number, process id, current time and a random number generated.

Returns : a newly created key, a gchar value.

gconf_escape_key ()

char*       gconf_escape_key                (const char *arbitrary_text,
                                             int len);

Escape arbitrary_text such that it's a valid key element (i.e. one part of the key path). The escaped key won't pass gconf_valid_key() because it isn't a whole key (i.e. it doesn't have a preceding slash), but prepending a slash to the escaped text should always result in a valid key.

arbitrary_text : some text in any encoding or format
len : length of arbitrary_text in bytes, or -1 if arbitrary_text is nul-terminated
Returns : a nul-terminated valid GConf key

gconf_unescape_key ()

char*       gconf_unescape_key              (const char *escaped_key,
                                             int len);

Converts a string escaped with gconf_escape_key() back into its original form.

escaped_key : a key created with gconf_escape_key()
len : length of escaped_key in bytes, or -1 if escaped_key is nul-terminated
Returns : the original string that was escaped to create escaped_key

gconf_engine_get_float ()

gdouble     gconf_engine_get_float          (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);

Requests the floating point number (GCONF_VALUE_FLOAT) stored at key. Automatically performs type-checking, so if a non-float is stored at key, an error is returned. On error, or if key is unset, 0.0 is returned.

conf : a GConfEngine.
key : key you want the value of.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : the value of key, or 0.0 if no value is obtained.

gconf_engine_get_int ()

gint        gconf_engine_get_int            (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);

Requests the integer (GCONF_VALUE_INT) stored at key. Automatically performs type-checking, so if a non-integer is stored at key, an error is returned. On error, or if key is unset, 0 is returned.

conf : a GConfEngine.
key : key you want the value of.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : the value of key, or 0 if no value is obtained.

gconf_engine_get_string ()

gchar*      gconf_engine_get_string         (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);

Requests the string (GCONF_VALUE_STRING) stored at key. Automatically performs type-checking, so if a non-string is stored at key, an error is returned. On error, or if key is unset, NULL is returned.

conf : a GConfEngine.
key : key you want the value of.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : allocated string (value of key), or NULL if no value is obtained.

gconf_engine_get_bool ()

gboolean    gconf_engine_get_bool           (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);

Requests the boolean value (GCONF_VALUE_BOOL) stored at key. Automatically performs type-checking, so if a non-bool is stored at key, an error is returned. On error, or if key is unset, FALSE is returned.

conf : a GConfEngine.
key : key you want the value of.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : the value of key, or FALSE if no value is obtained.

gconf_engine_get_schema ()

GConfSchema* gconf_engine_get_schema        (GConfEngine *conf,
                                             const gchar *key,
                                             GError **err);

Requests the schema (GCONF_VALUE_SCHEMA) stored at key. Automatically performs type-checking, so if a non-schema is stored at key, an error is returned. If no value is set or an error occurs, NULL is returned.

conf : a GConfEngine.
key : key you want the value of.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : the value of key as an allocated GConfSchema, or NULL if no value was obtained.

gconf_engine_get_list ()

GSList*     gconf_engine_get_list           (GConfEngine *conf,
                                             const gchar *key,
                                             GConfValueType list_type,
                                             GError **err);

Requests the list (GCONF_VALUE_LIST) stored at key. Automatically performs type-checking, so if a non-list is stored at key, or the list does not contain elements of type list_type, an error is returned. If no value is set or an error occurs, NULL is returned. Note that NULL is also the empty list, so if you need to distinguish the empty list from an unset value, you must use gconf_engine_get() to obtain a raw GConfValue.

Remember that GConf lists can only store primitive types: GCONF_VALUE_FLOAT, GCONF_VALUE_INT, GCONF_VALUE_BOOL, GCONF_VALUE_STRING, GCONF_VALUE_SCHEMA. Also remember that lists must be uniform, you may not mix types in the same list.

The type of the list elements depends on list_type. A GConfValue with type GCONF_VALUE_LIST normally stores a list of more GConfValue objects. gconf_engine_get_list() automatically converts to primitive C types. Thus, the list->data fields in the returned list contain:

GCONF_VALUE_INT The integer itself, converted with GINT_TO_POINTER()
GCONF_VALUE_BOOL The bool itself, converted with GINT_TO_POINTER()
GCONF_VALUE_FLOAT A pointer to gdouble, which should be freed with g_free()
GCONF_VALUE_STRING A pointer to gchar, which should be freed with g_free()
GCONF_VALUE_SCHEMA A pointer to GConfSchema, which should be freed with gconf_schema_free()

In the GCONF_VALUE_FLOAT and GCONF_VALUE_STRING cases, you must g_free() each list element. In the GCONF_VALUE_SCHEMA case you must gconf_schema_free() each element. In all cases you must free the list itself with g_slist_free().

conf : a GConfEngine.
key : key you want the value of.
list_type : type of each list element.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : an allocated list, with elements as described above.

gconf_engine_get_pair ()

gboolean    gconf_engine_get_pair           (GConfEngine *conf,
                                             const gchar *key,
                                             GConfValueType car_type,
                                             GConfValueType cdr_type,
                                             gpointer car_retloc,
                                             gpointer cdr_retloc,
                                             GError **err);

Requests the pair (GCONF_VALUE_PAIR) stored at key. Automatically performs type-checking, so if a non-pair is stored at key, or the pair does not have the right car_type and cdr_type, an error is returned. Remember that the car of a pair is its first value, and the cdr is its second value, in the Lisp tradition.

Remember that GConf pairs can only store primitive types: GCONF_VALUE_FLOAT, GCONF_VALUE_INT, GCONF_VALUE_BOOL, GCONF_VALUE_STRING, GCONF_VALUE_SCHEMA.

gconf_engine_get_pair() stores the two fields of the pair in the locations pointed to by car_retloc and cdr_retloc. The type of these pointers depends on the corresponding car_type and cdr_type:

GCONF_VALUE_INT pointer to gint
GCONF_VALUE_BOOL pointer to gboolean
GCONF_VALUE_FLOAT pointer to gdouble
GCONF_VALUE_STRING pointer to gchar*
GCONF_VALUE_SCHEMA pointer to GConfSchema*

In the GCONF_VALUE_STRING case, you must g_free() the string(s) stored in the return location(s). In the GCONF_VALUE_SCHEMA case you must gconf_schema_free() the returned schema. If there's an error or the value is unset, car_retloc and cdr_retloc are left unchanged.

gconf_engine_get_pair() returns TRUE on success.

An example of gconf_engine_get_pair() in action:

gdouble car = 10.0;
gchar* cdr  = NULL; 
GError* error = NULL;

if (!gconf_engine_get_pair(conf, "/foo", 
                    GCONF_VALUE_FLOAT,
                    GCONF_VALUE_STRING, 
                    &car, &cdr, &error))
  {
    /* Note: car/cdr should be untouched, because an error occurred */
    g_assert(error != NULL);
    fprintf(stderr, "Error: s\n", error->message);
    g_error_free(error);
    error = NULL;
  }
else
  {
    /* Note: car/cdr may be untouched even though there was no error, 
       if no value was set for "/foo"
     */
    printf("Found pair (g,s)\n", car, cdr);
    if (cdr != NULL)
      g_free(cdr);
  }

conf : a GConfEngine.
key : key you want the value of.
car_type : desired type of the pair's first field (car).
cdr_type : desired type of the pair's second field (cdr).
car_retloc : address of a return location for the car.
cdr_retloc : address of a return location for the cdr.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE on error.

gconf_engine_set_float ()

gboolean    gconf_engine_set_float          (GConfEngine *conf,
                                             const gchar *key,
                                             gdouble val,
                                             GError **err);

Change the value of key to val. Automatically creates the key if it didn't exist before (ie it was unset or it only had a default value). If the key already exists but doesn't store a float (GCONF_VALUE_FLOAT), gconf_engine_set_float() will fail.

conf : a GConfEngine.
key : key you want to set the value of.
val : new value of key.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE on error.

gconf_engine_set_int ()

gboolean    gconf_engine_set_int            (GConfEngine *conf,
                                             const gchar *key,
                                             gint val,
                                             GError **err);

Change the value of key to val. Automatically creates the key if it didn't exist before (ie it was unset or it only had a default value). If the key already exists but doesn't store an integer (GCONF_VALUE_INT), gconf_engine_set_int() will fail.

conf : a GConfEngine.
key : key you want to set the value of.
val : new value of key.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE on error.

gconf_engine_set_string ()

gboolean    gconf_engine_set_string         (GConfEngine *conf,
                                             const gchar *key,
                                             const gchar *val,
                                             GError **err);

Change the value of key to val. Automatically creates the key if it didn't exist before (ie it was unset or it only had a default value). If the key already exists but doesn't store a string (GCONF_VALUE_STRING), gconf_engine_set_string() will fail.

conf : a GConfEngine.
key : key you want to set the value of.
val : new value of key.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE on error.

gconf_engine_set_bool ()

gboolean    gconf_engine_set_bool           (GConfEngine *conf,
                                             const gchar *key,
                                             gboolean val,
                                             GError **err);

Change the value of key to val. Automatically creates the key if it didn't exist before (ie it was unset or it only had a default value). If the key already exists but but doesn't store a boolean (GCONF_VALUE_BOOL), gconf_engine_set_bool() will fail.

conf : a GConfEngine.
key : key you want to set the value of.
val : new value of key.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE on error.

gconf_engine_set_schema ()

gboolean    gconf_engine_set_schema         (GConfEngine *conf,
                                             const gchar *key,
                                             const GConfSchema *val,
                                             GError **err);

Change the value of key to val. Automatically creates the key if it didn't exist before (ie it was unset or it only had a default value). If the key already exists but doesn't store a schema value (GCONF_VALUE_SCHEMA), gconf_engine_set_schema() will fail.

conf : a GConfEngine.
key : key you want to set the value of.
val : new value of key.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE on error.

gconf_engine_set_list ()

gboolean    gconf_engine_set_list           (GConfEngine *conf,
                                             const gchar *key,
                                             GConfValueType list_type,
                                             GSList *list,
                                             GError **err);

Change the value of key to list of type list_type. Automatically creates the key if it didn't exist before (ie it was unset or it only had a default value). If the key already exists but doesn't store a list value (GCONF_VALUE_LIST), gconf_engine_set_list() will fail.

conf : a GConfEngine.
key : key you want to set the value of.
list_type : type of each list element.
list : new value of key.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE on error.

gconf_engine_set_pair ()

gboolean    gconf_engine_set_pair           (GConfEngine *conf,
                                             const gchar *key,
                                             GConfValueType car_type,
                                             GConfValueType cdr_type,
                                             gconstpointer address_of_car,
                                             gconstpointer address_of_cdr,
                                             GError **err);

Change the value of key to a pair of first type car_type and second type cdr_type . Automatically creates the key if it didn't exist before (ie it was unset or it only had a default value). If the key already exists but doesn't store a schema value (GCONF_VALUE_SCHEMA), gconf_engine_set_schema() will fail.

conf : a GConfEngine.
key : key you want to set the value of.
car_type : type of the pair's first field (car).
cdr_type : type of the pair's second field (cdr).
address_of_car : address of the car.
address_of_cdr : address of the cdr.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : TRUE on success, FALSE on error.

GConfEnumStringPair

typedef struct {
  gint enum_value;
  const gchar* str;
} GConfEnumStringPair;


gconf_string_to_enum ()

gboolean    gconf_string_to_enum            (GConfEnumStringPair lookup_table[],
                                             const gchar *str,
                                             gint *enum_value_retloc);

It's best to store enumeration values as strings rather than integers. This is robust against changes in the enumeration, and also human-readable. This function makes it more convenient to store enums as strings.

The first argument is a lookup table, typically declared statically as follows:

static GConfEnumStringPair foo_enum_lookup_table[] = {
  { FOO_BLAH, "Blah" },
  { FOO_BAR,  "Bar"  },
  { 0, NULL }
};

Note that the last element of the table is { 0, NULL }. Typically the strings you use should be semi-human-readable, for GTK+ and GNOME stripping off the library prefix and converting to StudlyCaps is the recommended convention.

The function returns TRUE if a match for the string is found, and if a match is found the enum value is placed in enum_value_retloc.

lookup_table : a lookup table mapping enum values to strings.
str : the string to convert to an enum value.
enum_value_retloc : the address of an enum variable.
Returns : TRUE if a match was found.

gconf_enum_to_string ()

const gchar* gconf_enum_to_string           (GConfEnumStringPair lookup_table[],
                                             gint enum_value);

See gconf_string_to_enum() for background information on this function.

lookup_table : a lookup table mapping enum values to strings.
enum_value : the enumeration value to convert to a string.
Returns : a pointer to the proper string in the lookup table, or NULL if no match was found.

gconf_clear_cache ()

void        gconf_clear_cache               (GConfEngine *conf,
                                             GError **err);

In case of a local GConfEngine, this function calls gconf_sources_clear_cache() to clear the cache from the source. Otherwise it obtains the configuration database using gconf_engine_get_database() and clears the configuration database cache using ConfigDatabase_clear_cache().

conf : a GConfEngine.
err : the return location for an allocated GError, or NULL to ignore errors.

gconf_synchronous_sync ()

void        gconf_synchronous_sync          (GConfEngine *conf,
                                             GError **err);

In case of a local GConfEngine, this function syncs up all the gconf sources calling gconf_synchronous_sync(). Otherwise it obtains the configuration database using gconf_engine_get_database() and syncs up the database calling ConfigDatabase_synchronous_sync().

conf : a GConfEngine.
err : the return location for an allocated GError, or NULL to ignore errors.

gconf_engine_get_full ()

GConfValue* gconf_engine_get_full           (GConfEngine *conf,
                                             const gchar *key,
                                             const gchar *locale,
                                             gboolean use_schema_default,
                                             gboolean *is_default_p,
                                             gboolean *is_writable_p,
                                             GError **err);

Returns the GConfValue of a key and the associated GConfEntry fields depending on the parameters passed.

conf : a GConfEngine.
key : the key whose value is to be obtained.
locale : the preferred locale (as in the locale related environment variables) orNULL if no locale is to be passed.
use_schema_default : a gboolean value, indicating whether schema information is to be used as the default value.
is_default_p : a gpointer if the is_default field of the GConfEntry is required, NULL otherwise.
is_writable_p : a gpointer if the is_writable field of the GConfEntry is required, NULL otherwise.
err : the return location for an allocated GError, or NULL to ignore errors.
Returns : the GConfValue.