int connection_readline(urg_connection_t *connection, char *data, int max_size, int timeout)
���s�����܂ł̎�M
urg_connection_t connection
int urg_raw_readline(urg_t *urg, char *data, int max_data_size, int timeout)
int connection_write(urg_connection_t *connection, const char *data, int size)
���M
int connection_read(urg_connection_t *connection, char *data, int max_size, int timeout)
��M
int urg_raw_read(urg_t *urg, char *data, int max_data_size, int timeout)
int urg_raw_write(urg_t *urg, const char *data, int data_size)