Linux设置串口速率为非标准速率

pyserial是这样实现的

# baudrate ioctls
TCGETS2 = 0x802C542A
TCSETS2 = 0x402C542B
BOTHER = 0o010000


        def _set_special_baudrate(self, baudrate):
            # right size is 44 on x86_64, allow for some growth
            buf = array.array('i', [0] * 64)
            try:
                # get serial_struct
                fcntl.ioctl(self.fd, TCGETS2, buf)
                # set custom speed
                buf[2] &= ~termios.CBAUD
                buf[2] |= BOTHER
                buf[9] = buf[10] = baudrate

                # set serial_struct
                fcntl.ioctl(self.fd, TCSETS2, buf)
            except IOError as e:
                raise ValueError('Failed to set custom baud rate ({}): {}'.format(baudrate, e))