Problems with serial ports

Hello. My problem is that when I try to read the serial port I don’t receive any data from my PC. I configured the ports, as seen in the attached file. And the error that I get with perror’s function in read is “Resource temporally unavailable”. Besides, I’ve noticed that when I run the program (attached file) the configuration that I have made him to serial ports is not done, because I’m connected via ssh to the IP of ConectCore 9c and I do an instruction of the system to know the configuration of the port and I get different speed, input, etc

Attached file:
Note:I have also tested with FD_ZERO, FD_SET, and the function “select”
int main(void)
int fd,nbytes;
char buf[255];
struct termios options;

fd = open("/dev/ttyS0", O_RDWR | O_NOCTTY | O_NDELAY);
fcntl(fd, F_SETFL, 0);

	tcgetattr(fd, &options);

cfsetispeed(&options, B115200);
	cfsetospeed(&options, B115200);

	options.c_cflag |= (CLOCAL | CREAD);
options.c_cflag &= ~PARENB
options.c_cflag &= ~CSTOPB
options.c_cflag &= ~CSIZE;
options.c_cflag |= CS8;

	options.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG);

options.c_oflag &= ~OPOST;

tcsetattr(fd, TCSANOW, &options);

nbytes = read(fd, buf,255);

return 1;


Thank you very much. I await your response.