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GConf Reference Manual | ![]() |
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enum GConfClientPreloadType; enum GConfClientErrorHandlingMode; void (*GConfClientNotifyFunc) (GConfClient *client, guint cnxn_id, GConfEntry *entry, gpointer user_data); void (*GConfClientErrorHandlerFunc) (GConfClient *client, GError *error); #define GCONF_CLIENT (obj) GConfClient* gconf_client_get_default (void); GConfClient* gconf_client_get_for_engine (GConfEngine *engine); void gconf_client_add_dir (GConfClient *client, const gchar *dir, GConfClientPreloadType preload, GError **err); void gconf_client_remove_dir (GConfClient *client, const gchar *dir, GError **err); guint gconf_client_notify_add (GConfClient *client, const gchar *namespace_section, GConfClientNotifyFunc func, gpointer user_data, GFreeFunc destroy_notify, GError **err); void gconf_client_notify_remove (GConfClient *client, guint cnxn); void gconf_client_notify (GConfClient *client, const char *key); void gconf_client_set_error_handling (GConfClient *client, GConfClientErrorHandlingMode mode); void gconf_client_set_global_default_error_handler (GConfClientErrorHandlerFunc func); void gconf_client_clear_cache (GConfClient *client); void gconf_client_preload (GConfClient *client, const gchar *dirname, GConfClientPreloadType type, GError **err); void gconf_client_set (GConfClient *client, const gchar *key, const GConfValue *val, GError **err); GConfValue* gconf_client_get (GConfClient *client, const gchar *key, GError **err); GConfValue* gconf_client_get_without_default (GConfClient *client, const gchar *key, GError **err); GConfEntry* gconf_client_get_entry (GConfClient *client, const gchar *key, const gchar *locale, gboolean use_schema_default, GError **err); GConfValue* gconf_client_get_default_from_schema (GConfClient *client, const gchar *key, GError **err); gboolean gconf_client_unset (GConfClient *client, const gchar *key, GError **err); gboolean gconf_client_recursive_unset (GConfClient *client, const char *key, GConfUnsetFlags flags, GError **err); GSList* gconf_client_all_entries (GConfClient *client, const gchar *dir, GError **err); GSList* gconf_client_all_dirs (GConfClient *client, const gchar *dir, GError **err); void gconf_client_suggest_sync (GConfClient *client, GError **err); gboolean gconf_client_dir_exists (GConfClient *client, const gchar *dir, GError **err); gboolean gconf_client_key_is_writable (GConfClient *client, const gchar *key, GError **err); gdouble gconf_client_get_float (GConfClient *client, const gchar *key, GError **err); gint gconf_client_get_int (GConfClient *client, const gchar *key, GError **err); gchar* gconf_client_get_string (GConfClient *client, const gchar *key, GError **err); gboolean gconf_client_get_bool (GConfClient *client, const gchar *key, GError **err); GConfSchema* gconf_client_get_schema (GConfClient *client, const gchar *key, GError **err); GSList* gconf_client_get_list (GConfClient *client, const gchar *key, GConfValueType list_type, GError **err); gboolean gconf_client_get_pair (GConfClient *client, const gchar *key, GConfValueType car_type, GConfValueType cdr_type, gpointer car_retloc, gpointer cdr_retloc, GError **err); gboolean gconf_client_set_float (GConfClient *client, const gchar *key, gdouble val, GError **err); gboolean gconf_client_set_int (GConfClient *client, const gchar *key, gint val, GError **err); gboolean gconf_client_set_string (GConfClient *client, const gchar *key, const gchar *val, GError **err); gboolean gconf_client_set_bool (GConfClient *client, const gchar *key, gboolean val, GError **err); gboolean gconf_client_set_schema (GConfClient *client, const gchar *key, const GConfSchema *val, GError **err); gboolean gconf_client_set_list (GConfClient *client, const gchar *key, GConfValueType list_type, GSList *list, GError **err); gboolean gconf_client_set_pair (GConfClient *client, const gchar *key, GConfValueType car_type, GConfValueType cdr_type, gconstpointer address_of_car, gconstpointer address_of_cdr, GError **err); void gconf_client_error (GConfClient *client, GError *error); void gconf_client_unreturned_error (GConfClient *client, GError *error); void gconf_client_value_changed (GConfClient *client, const gchar *key, GConfValue *value); gboolean gconf_client_commit_change_set (GConfClient *client, GConfChangeSet *cs, gboolean remove_committed, GError **err); GConfChangeSet* gconf_client_reverse_change_set (GConfClient *client, GConfChangeSet *cs, GError **err); GConfChangeSet* gconf_client_change_set_from_currentv (GConfClient *client, const gchar **keys, GError **err); GConfChangeSet* gconf_client_change_set_from_current (GConfClient *client, GError **err, const gchar *first_key, ...);
GConfClient adds the following features to plain GConf:
A client-side cache for a specified list of directories you're interested in. You can "preload" entire directories into the cache, speeding things up even more.
Some automatic error handling, if you request it.
Signals when a value changes or an error occurs.
If you use GConfClient, you should not use the underlying GConfEngine
directly, or you'll break things. This is why there's no
gconf_client_get_engine()
function; in fact, if you create the GConfClient with
gconf_client_get_default()
, there is no (legitimate) way to obtain a pointer to the
underlying GConfEngine. If you create a GConfClient from an existing engine,
you'll have to be disciplined enough to avoid using that engine directly.
[1]
A GConfClient has a list of directories that it "watches." These directories are optionally pre-loaded into the cache, and monitored in order to emit the value_changed signal. The GConfClient can also be used to access directories not in the list, but those directories won't be preloaded and the "value_changed" signal won't be emitted for them.
There are two error-related signals in GConfClient. The first is plain "error"; it's emitted anytime an error occurs. The second is "unreturned_error"; this signal is emitted if you pass NULL as the GError** to any GConfClient function. The idea is that you can have a global error handler attached to the "unreturned_error" signal; if you want to use this handler, you don't need to use the normal GConf error handling mechanism. However, if you ever need to handle errors for a specific function call, you can override the global handler by passing a non-NULL GError** to the function. If you want an error handler that's always invoked, use the "error" signal.
The "value_changed" signal is emitted whenever the server notifies your client
program that a value has changed in the GConf database. There's one problem with
this signal: the signal handler has to use strcmp()
to determine whether the
changed value is the one it was interested in. If you are interested in lots of
values, then every time a value changes you'll be making lots of calls to
strcmp()
and getting O(n) performance. gconf_client_notify_add()
is a superior
interface in most cases for this reason. Note that calling gconf_client_set()
and its relatives will cause "value_changed" to be emitted, but "value_changed"
is also emitted if another process changes the value.
Most of the GConfClient interface mirrors the functions you'd use to manipulate
a GConfEngine (gconf_engine_get()
and gconf_client_get()
, for example). These should
all work just like the GConfEngine versions, except that they use the cache
from GConfClient and emit the GConfClient signals.
As always with GConf, applications based on GConfClient should use a model-controller-view architecture. Typically, this means that areas of your application affected by a setting will monitor the relevant key and update themselves when necessary. The preferences dialog will simply change keys, allowing GConf to notify the rest of the application that changes have occurred. Here the application proper is the "view," GConf is the "model", and the preferences dialog is the "controller." In no case should you do this:
gconf_client_set(client, key, value); application_update_to_reflect_setting();
This breaks if a setting is changed outside your application—or even from a different part of your application. The correct way (in pseudo-code) is:
/* At application startup */ gconf_client_notify_add(client, key, application_update_to_reflect_setting, data); /* From preferences dialog */ gconf_client_set(client, key, value);
See the example programs that come with GConf for more details.
typedef enum { /*< prefix=GCONF_CLIENT >*/ GCONF_CLIENT_PRELOAD_NONE, /* don't preload anything */ GCONF_CLIENT_PRELOAD_ONELEVEL, /* load entries directly under the directory. */ GCONF_CLIENT_PRELOAD_RECURSIVE /* recurse the directory tree; possibly quite expensive! */ } GConfClientPreloadType;
The GConfClientPreloadType is used to tell GConfClient how to preload one of
its directories. As a rule of thumb, if you plan to get the value of almost all the
keys in a directory, preloading that directory will probably enhance
performance. If you plan to use only half the keys, preloading is likely a bad
idea. GCONF_CLIENT_PRELOAD_NONE
specifies that no preload occurs,
GCONF_CLIENT_PRELOAD_ONELEVEL
loads the immediate children of the directory,
GCONF_CLIENT_PRELOAD_RECURSIVE
loads all children of the
directory and its subdirectories, recursively.
typedef enum { /*< prefix=GCONF_CLIENT >*/ GCONF_CLIENT_HANDLE_NONE, GCONF_CLIENT_HANDLE_UNRETURNED, GCONF_CLIENT_HANDLE_ALL } GConfClientErrorHandlingMode;
GConfClientErrorHandlingMode is used to control GConfClient's default error
handling. GConfClient can pop up a dialog in the default signal handler for
"error" or "unreturned_error." You can specify that no errors are handled, only
unreturned errors are handled, or all errors are handled with this enumeration.
You can prevent specific errors from being handled automatically by stopping the
signal emission before the default signal handler is called (see the GLib
documentation, g_signal_stop_emission_by_name()
for example).
void (*GConfClientNotifyFunc) (GConfClient *client, guint cnxn_id, GConfEntry *entry, gpointer user_data);
This is the signature of a user function added with gconf_client_notify_add()
.
The notify function is invoked when the value of a key changes. The value
argument is the new value, or NULL if the key was unset. The
value
argument should not be modified, and should be copied if you want to keep
it around (the GConfClient will destroy it sometime after your notify function
is called).
client : |
the GConfClient notifying us. |
cnxn_id : |
connection ID from gconf_client_notify_add() .
|
entry : |
a GConfEntry. |
user_data : |
user data from gconf_client_notify_add() .
|
void (*GConfClientErrorHandlerFunc) (GConfClient *client, GError *error);
This is the signature of a user function which needs to be called for error handling.
client : |
a GConfClient. |
error : |
the return location for an allocated GError, or NULL to ignore errors. |
#define GCONF_CLIENT(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GCONF_TYPE_CLIENT, GConfClient))
Casts a pointer to a GConfClient*.
obj : |
a GConfClient. |
GConfClient* gconf_client_get_default (void);
Creates a new GConfClient using the default GConfEngine. Normally this is the engine you want. If someone else is already using the default GConfClient, this function returns the same one they're using, but with the reference count incremented. So you have to unref either way.
It's important to call g_type_init()
before using this GObject, to initialize the type system.
Returns : | a new GConfClient. g_object_unref() when you're done.
|
GConfClient* gconf_client_get_for_engine (GConfEngine *engine);
Creates a new GConfClient with a specific GConfEngine. Only specialized
configuration-related programs should need to call this function. The
returned GConfClient should be unref'd when you're done with g_object_unref()
.
Remember to avoid using the GConfEngine directly once you have a GConfClient
wrapper.
engine : |
the GConfEngine to use. |
Returns : | a new GConfClient. |
void gconf_client_add_dir (GConfClient *client, const gchar *dir, GConfClientPreloadType preload, GError **err);
Add a directory to the list of directories the GConfClient will watch. Any changes to keys below this directory will cause the "value_changed" signal to be emitted. When you add the directory, you can request that the GConfClient preload its contents; see GConfClientPreloadType for details.
Added directories may not overlap. That is, if you add "/foo", you may not add
"/foo/bar". However you can add "/foo" and "/bar". You can also add "/foo"
multiple times; if you add a directory multiple times, it will not be removed
until you call gconf_client_remove_dir()
an equal number of times.
client : |
a GConfClient. |
dir : |
directory to add to the list. |
preload : |
degree of preload. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
void gconf_client_remove_dir (GConfClient *client, const gchar *dir, GError **err);
Remove a directory from the list created with gconf_client_add_dir()
. If any
notifications have been added below this directory with
gconf_client_notify_add()
, those notifications will be disabled until you re-add
the removed directory. Note that if a directory has been added multiple times,
you must remove it the same number of times before the remove takes effect.
client : |
a GConfClient. |
dir : |
directory to remove. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
guint gconf_client_notify_add (GConfClient *client, const gchar *namespace_section, GConfClientNotifyFunc func, gpointer user_data, GFreeFunc destroy_notify, GError **err);
Request notification of changes to namespace_section
. This includes the key
namespace_section
itself, and any keys below it (the behavior is identical to
gconf_engine_notify_add()
, but while gconf_engine_notify_add()
places a notification request
on the server for every notify function, GConfClient requests server
notification for directories added with gconf_client_add_dir()
and keeps the
list of GConfClientNotifyFunc on the client side).
For the notification to happen, namespace_section
must be equal to or below one
of the directories added with gconf_client_add_dir()
. You can still call
gconf_client_notify_add()
for other directories, but no notification will be
received until you add a directory above or equal to namespace_section
. One
implication of this is that gconf_client_remove_dir()
temporarily disables
notifications that were below the removed directory.
The function returns a connection ID you can use to call
gconf_client_notify_remove()
.
See the description of GConfClientNotifyFunc for details on how the notification function is called.
client : |
a GConfClient. |
namespace_section : |
where to listen for changes. |
func : |
function to call when changes occur. |
user_data : |
user data to pass to func .
|
destroy_notify : |
function to call on user_data when the notify is removed or the GConfClient is destroyed, or NULL for none.
|
err : |
the return location for an allocated GError, or NULL to ignore errors. |
Returns : | a connection ID for removing the notification. |
void gconf_client_notify_remove (GConfClient *client, guint cnxn);
Remove a notification using the ID returned from
gconf_client_notify_add()
. Invokes the destroy notify function on the
notification's user data, if appropriate.
client : |
a GConfClient. |
cnxn : |
connection ID. |
void gconf_client_notify (GConfClient *client, const char *key);
Emits the "value-changed" signal and notifies listeners as if key
had been
changed
client : |
a GConfClient. |
key : |
the key that has changed. |
Since 2.4.
void gconf_client_set_error_handling (GConfClient *client, GConfClientErrorHandlingMode mode);
Controls the default error handling for GConfClient. See GConfClientErrorHandlingMode and GConfClientParentWindowFunc for details on this.
client : |
a GConfClient. |
mode : |
error handling mode. |
void gconf_client_set_global_default_error_handler (GConfClientErrorHandlerFunc func);
Set func
as the default error handler for the GConfClient. This handler would be called
for all GConfClient internal errors.
func : |
pointer to the function to be called for error handling. |
void gconf_client_clear_cache (GConfClient *client);
Dumps everything out of the GConfClient client-side cache. If you know you're done using the GConfClient for a while, you can call this function to save some memory.
client : |
a GConfClient. |
void gconf_client_preload (GConfClient *client, const gchar *dirname, GConfClientPreloadType type, GError **err);
Preloads a directory. Normally you do this when you call gconf_client_add_dir()
,
but if you've called gconf_client_clear_cache()
there may be a reason to do it
again.
client : |
a GConfClient. |
dirname : |
directory to preload. |
type : |
degree of preload. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
void gconf_client_set (GConfClient *client, const gchar *key, const GConfValue *val, GError **err);
Sets the value of a configuration key. Just like gconf_engine_set()
, but uses
GConfClient caching and error-handling features. The val
argument will not be
modified.
client : |
a GConfClient. |
key : |
key to set. |
val : |
new value. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
GConfValue* gconf_client_get (GConfClient *client, const gchar *key, GError **err);
Gets the value of a configuration key. Just like gconf_engine_get()
, but uses
GConfClient caching and error-handling features.
client : |
a GConfClient. |
key : |
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. |
GConfValue* gconf_client_get_without_default (GConfClient *client, const gchar *key, GError **err);
Gets the value of a configuration key. Just like gconf_client_get()
but doesn't look for a default value if the key is unset.
client : |
a GConfClient. |
key : |
key to get. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
Returns : | newly-allocated GConfValue, or NULL if unset (even if a default exists). |
GConfEntry* gconf_client_get_entry (GConfClient *client, const gchar *key, const gchar *locale, gboolean use_schema_default, GError **err);
Obtains the full GConfEntry for a value. Just like gconf_engine_get_entry()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
key : |
key to get. |
locale : |
preferred locale (as in the locale-related environment variables). |
use_schema_default : |
indicates whether to look for a default value when the key is unset. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
Returns : | a GConfEntry. |
GConfValue* gconf_client_get_default_from_schema (GConfClient *client, 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_client_get()
, gconf_engine_client_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. Just like gconf_engine_get_default_from_schema()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
key : |
key to get. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
Returns : | newly-allocated GConfValue, or NULL if the key has no default value in its schema. |
gboolean gconf_client_unset (GConfClient *client, 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.
Just like gconf_engine_unset()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
key : |
key to unset. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
Returns : | TRUE on success, FALSE on error. |
gboolean gconf_client_recursive_unset (GConfClient *client, const char *key, GConfUnsetFlags flags, GError **err);
Unsets all keys below key
, including key
itself. If any unset fails, continues on to unset
as much as it can. The first failure is returned in err
. Just like gconf_engine_recursive_unset()
,
but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
key : |
a key or directory name to be unset. |
flags : |
change how the unset is done. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
Returns : | TRUE on success, FALSE on error. |
Since 2.4.
GSList* gconf_client_all_entries (GConfClient *client, const gchar *dir, GError **err);
Lists the key-value pairs in dir
. Does not list subdirectories; for
that use gconf_client_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.
Just like gconf_engine_all_entries()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
dir : |
directory to list. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
Returns : | List of GConfEntry. |
GSList* gconf_client_all_dirs (GConfClient *client, 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.
Just like gconf_engine_all_dirs()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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. |
void gconf_client_suggest_sync (GConfClient *client, 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.
Just like gconf_engine_suggest_sync()
.
client : |
a GConfClient. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
gboolean gconf_client_dir_exists (GConfClient *client, const gchar *dir, GError **err);
Queries whether the directory dir
exists in the GConf
database. Returns TRUE or FALSE.
Just like gconf_engine_dir_exists()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
dir : |
directory to check for |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
Returns : | TRUE or FALSE. |
gboolean gconf_client_key_is_writable (GConfClient *client, const gchar *key, GError **err);
Checks whether the key is writable.
client : |
a GConfClient. |
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. |
gdouble gconf_client_get_float (GConfClient *client, 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.
Just like gconf_engine_get_float()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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.
|
gint gconf_client_get_int (GConfClient *client, 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.
Just like gconf_engine_get_int()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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.
|
gchar* gconf_client_get_string (GConfClient *client, 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.
Just like gconf_engine_get_string()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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.
|
gboolean gconf_client_get_bool (GConfClient *client, 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.
Just like gconf_engine_get_bool()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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.
|
GConfSchema* gconf_client_get_schema (GConfClient *client, 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.
Just like gconf_engine_get_schema()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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.
|
GSList* gconf_client_get_list (GConfClient *client, 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_client_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_client_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()
.
Just like gconf_engine_get_list()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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. |
gboolean gconf_client_get_pair (GConfClient *client, 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_client_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_client_get_pair()
returns TRUE on success.
An example of gconf_client_get_pair()
in action:
gdouble car = 10.0; gchar* cdr = NULL; GError* error = NULL; if (!gconf_client_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); }
client : |
a GConfClient. |
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. |
gboolean gconf_client_set_float (GConfClient *client, 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_client_set_float()
will fail.
Just like gconf_engine_set()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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. |
gboolean gconf_client_set_int (GConfClient *client, 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_client_set_int()
will fail.
Just like gconf_engine_set()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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. |
gboolean gconf_client_set_string (GConfClient *client, 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_client_set_string()
will fail.
Just like gconf_engine_set()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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. |
gboolean gconf_client_set_bool (GConfClient *client, 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_client_set_bool()
will fail.
Just like gconf_engine_set()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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. |
gboolean gconf_client_set_schema (GConfClient *client, 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_client_set_schema()
will fail.
Just like gconf_engine_set()
, but uses GConfClient caching and error-handling features.
client : |
a GConfClient. |
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. |
gboolean gconf_client_set_list (GConfClient *client, const gchar *key, GConfValueType list_type, GSList *list, GError **err);
Changes the value of key
to a list
of type list_type
. Automatically creates the key
if it didn't exist before
(ie it was unset or it had a default value). If the key already exists but doesn't store a list value
(GCONF_VALUE_LIST), gconf_client_set_list()
will fail.
client : |
a GConfClient. |
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. |
gboolean gconf_client_set_pair (GConfClient *client, const gchar *key, GConfValueType car_type, GConfValueType cdr_type, gconstpointer address_of_car, gconstpointer address_of_cdr, GError **err);
Changes the value of key
to a pair with the first field of type car_type
and the second field of type cdr_type
.
Automatically creates the key if it didn't exist before (ie it was unset or it had a default value). If the key
already exists but doesn't store a pair value (GCONF_VALUE_PAIR), gconf_client_set_pair()
will fail.
client : |
a GConfClient. |
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. |
void gconf_client_error (GConfClient *client, GError *error);
Emits the "error" signal. Rarely useful.
client : |
a GConfClient. |
error : |
error to pass to signal handlers. |
void gconf_client_unreturned_error (GConfClient *client, GError *error);
Emits the "unreturned_error" signal. Rarely useful.
client : |
a GConfClient. |
error : |
error to pass to signal handlers. |
void gconf_client_value_changed (GConfClient *client, const gchar *key, GConfValue *value);
Emits the "value_changed" signal. Rarely useful.
client : |
a GConfClient. |
key : |
key to pass to signal handlers. |
value : |
value of key to pass to signal handlers.
|
gboolean gconf_client_commit_change_set (GConfClient *client, GConfChangeSet *cs, gboolean remove_committed, GError **err);
Applies the changes in the change set to the GConfClient passed as
the first argument. If remove_committed
is TRUE,
then any successfully-committed changes are removed from the change
set. If remove_committed
is FALSE, the
GConfChangeSet is left unmodified.
If any set or unset operation results in an error, then processing
terminates and the error is returned in err
(unless err
was
NULL). If remove_committed
was
TRUE, then all the changes committed before the error
occurred will have been removed from the set. If any error occurs,
FALSE is returned.
client : |
a GConfClient. |
cs : |
a GConfChangeSet. |
remove_committed : |
whether to remove successfully-committed changes from the set. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
Returns : | TRUE on success, FALSE if an error occurs. |
GConfChangeSet* gconf_client_reverse_change_set (GConfClient *client, GConfChangeSet *cs, GError **err);
Creates a change set that would reverse cs
. That is, for each change in cs
,
save the current state of that key in the returned change set.
client : |
a GConfClient. |
cs : |
change set to create the reverse of. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
Returns : | a new change set that would restore the current state of each key in cs .
|
GConfChangeSet* gconf_client_change_set_from_currentv (GConfClient *client, const gchar **keys, GError **err);
Creates a change set that will change the keys in
NULL-terminated array keys
to their current state. Use this to
save the current state of a collection of keys; then you can later revert to the
current state by committing the returned change set.
client : |
a GConfClient. |
keys : |
NULL-terminated array of key names. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
Returns : | new change set that changes all the keys to their current state.
|
GConfChangeSet* gconf_client_change_set_from_current (GConfClient *client, GError **err, const gchar *first_key, ...);
Convenient varargs version of gconf_client_change_set_from_currentv()
.
client : |
a GConfClient. |
err : |
the return location for an allocated GError, or NULL to ignore errors. |
first_key : |
first key to save the current state of. |
... : |
NULL-terminated list of additional keys. |
Returns : | new change set that changes all the keys to their current state. |
[1] This is all a white lie; some direct GConfEngine operations are safe. But it's complicated to know which, and if an operation isn't safe the resulting bugs will mangle the cache and cause weird bugs at an indeterminate time in the future; you don't want to risk this situation.