+DBUS_EXPORT
+dbus_bool_t dbus_pending_call_allocate_data_slot (dbus_int32_t *slot_p);
+DBUS_EXPORT
+void dbus_pending_call_free_data_slot (dbus_int32_t *slot_p);
+DBUS_EXPORT
+dbus_bool_t dbus_pending_call_set_data (DBusPendingCall *pending,
+ dbus_int32_t slot,
+ void *data,
+ DBusFreeFunction free_data_func);
+DBUS_EXPORT
+void* dbus_pending_call_get_data (DBusPendingCall *pending,
+ dbus_int32_t slot);