int _bt_rfcomm_connect_using_uuid(bluetooth_device_address_t *device_address, char *remote_uuid);
int _bt_rfcomm_connect_using_channel(bluetooth_device_address_t *device_address, char *chan_str);
int _bt_rfcomm_socket_listen(char *svc_name, char *uuid, bool accept);
int _bt_rfcomm_connect_using_uuid(bluetooth_device_address_t *device_address, char *remote_uuid);
int _bt_rfcomm_connect_using_channel(bluetooth_device_address_t *device_address, char *chan_str);
int _bt_rfcomm_socket_listen(char *svc_name, char *uuid, bool accept);