sw-online
gboolean sw_is_online (void);
void
void (*SwOnlineNotify) (gboolean online, gpointer user_data);
gboolean online
gpointer user_data
void sw_online_add_notify (SwOnlineNotify callback, gpointer user_data);
SwOnlineNotify callback
void sw_online_remove_notify (SwOnlineNotify callback, gpointer user_data);