[En-Nut-Discussion] Uart, detecting if there are characters waiting in the queue without blocking

[Brett Abbott]

Hi

I have set up a uart FILE device.  Is there a simple method to check if 
there are incoming characters in the buffer waiting to be read?  From 
time to time I wish to see if there are characters waiting but dont wish 
to block if no characters have been received.  Perhaps there is a simple 
means to check incoming queue length?

In particular, Im prompting the user to press a key (via the uart) 
within 10 seconds in response to an event.  If I can help it, I'd rather 
not use a blocking function call.

The uart has been inititalised in the normal way.....

   NutRegisterDevice(&devUart0, 0, 0);
   uart = fopen("uart0", "r+b");
    _ioctl(_fileno(uart), UART_SETSPEED, &baud);

Any Help appreciated.
Brett

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