Use the device /dev/cu.usbserial-A601L9OC
instead, and set the speed to 9600 baud also. Here's an example from Magnus' macrumor post:
strcpy(bsdPath, "/dev/cu.usbserial-A601L9OC");
fileDescriptor = open(bsdPath, O_RDWR);
if (-1 == fileDescriptor)
{
return EX_IOERR;
}
struct termios theTermios;
memset(&theTermios, 0, sizeof(struct termios));
cfmakeraw(&theTermios);
cfsetspeed(&theTermios, 9600);
theTermios.c_cflag = CREAD | CLOCAL; // turn on READ and ignore modem control lines
theTermios.c_cflag |= CS8;
theTermios.c_cc[VMIN] = 0;
theTermios.c_cc[VTIME] = 10; // 1 sec timeout
int ret = ioctl(fileDescriptor, TIOCSETA, &theTermios);
ret = read(fileDescriptor, &c, 1);