np_client_free np_client_new np_client_start_service np_client_t NP_DISK_USAGE_CHANGED np_error_t np_notify_cb_t np_observe_notification np_observe_notifications np_post_notification np_set_notify_callback

np_set_notify_callback() np_error_t np_set_notify_callback ( np_client_t  client, np_notify_cb_t  notify_cb, void *  userdata  ) This function allows an application to define a callback function that will be called when a notification has been received. It will start a thread that polls for notifications and calls the callback function if a notification has been received. In case of an error condition when polling for notifications - e.g. device disconnect - the thread will call the callback function with an empty notification "" and terminate itself. Parameters client the NP client notify_cb pointer to a callback function or NULL to de-register a previously set callback function. user_data Pointer that will be passed to the callback function as user data. If notify_cb is NULL, this parameter is ignored. Note Only one callback function can be registered at the same time; any previously set callback function will be removed automatically. Returns NP_E_SUCCESS when the callback was successfully registered, NP_E_INVALID_ARG when client is NULL, or NP_E_UNKNOWN_ERROR when the callback thread could no be created.