added
 * speed_t cfgetispeed(const struct termios* termios)
 * speed_t cfgetospeed(const struct termios* termios)
 * int cfsetispeed(struct termios* termios, speed_t ispeed)
 * int cfsetospeed(struct termios* termios, speed_t ospeed)
 * int tcdrain(int file)
 * int tcflow(int file, int flags)
 * int tcflush(int file, int flags)
"added reentrancy"
likeposix now needs to be initialized nefore use.