Hello all!

I am having some trouble reading some data from a serial port I opened the following way. I've used this instance of code plenty of times and all worked fine, but now, for some reason that I cant figure out, I am completely unable to read anything from the serial port.

I am able to write and all is correctly received on the other end, but the replies (which are correctly sent) are never received (No, the cables are all ok ;) )

The code I used to open the serial port is the following:

fd = open("/dev/ttyUSB0", O_RDWR | O_NONBLOCK | O_NOCTTY);
if (fd == -1)
{
    Aviso("Unable to open port");
    return (fd);
}
else
{
    //Get the current options for the port...
    bzero(&options, sizeof(options)); /* clear struct for new port settings */
    tcgetattr(fd, &options);

    /*-- Set baud rate -------------------------------------------------------*/
    if (cfsetispeed(&options, SerialBaudInterp(BaudRate))==-1)
        perror("On cfsetispeed:");
    if (cfsetospeed(&options, SerialBaudInterp(BaudRate))==-1)
        perror("On cfsetospeed:");

    //Enable the receiver and set local mode...
    options.c_cflag |= (CLOCAL | CREAD);
    options.c_cflag &= ~PARENB; /* Parity disabled */
    options.c_cflag &= ~CSTOPB;
    options.c_cflag &= ~CSIZE;  /* Mask the character size bits */
    options.c_cflag |= SerialDataBitsInterp(8);           /* CS8 - Selects 8 data bits */
    options.c_cflag &= ~CRTSCTS;    		                // disable hardware flow control
    options.c_iflag &= ~(IXON | IXOFF | IXANY);           // disable XON XOFF (for transmit and receive)
    options.c_cflag |= CRTSCTS;                         /* enable hardware flow control */

    options.c_cc[VMIN] = 0; 	//min carachters to be read
    options.c_cc[VTIME] = 0;    //Time to wait for data (tenths of seconds)

    //Set the new options for the port...
    tcflush(fd, TCIFLUSH);
    if (tcsetattr(fd, TCSANOW, &options)==-1)
    {
        perror("On tcsetattr:");
    }

    PortOpen[ComPort] = fd;
}

return PortOpen[ComPort];

After the port is initializeed I write some stuff to it through simple write command...

int nc = write(hCom, txchar, n);

where hCom is the file descriptor (and it's ok), and (as I said) this works. But... when I do a read afterwards, I get a "Resource Temporarily Unavailable" error from errno.

I tested select to see when the file descriptor had something t read... but it always times out!

I read data like this:

ret = read(hCom, rxchar, n);

and I always get an EAGAIN and I have no idea why.

All help would be appreciated.

Cheers