IOCTL_FARC_GET_RXSTATUS

Purpose: check out if any packets have been received

Parameter:
IN:   -
OUT:  UCHAR (size of output buffer > = 1 byte)

Comment:
This function returns 0, if no unread packets available otherwise 1.

Possible errors (see also Error codes):
E_FARC_INVALID_HANDLE
E_FARC_BUFFER_TOO_SMALL

Example:
Note, that the following example is only a fragment. It is recommended, that the driver is opened in asynchronous mode and a handle to the driver is available.

OVERLAPPED overlapped;
DWORD read, err;
BOOL ret;
UCHAR rxStatus;

overlapped.Offset = 0;
overlapped.OffsetHigh = 0;
overlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);

...
ret = DeviceIoControl(drvhandle,
    IOCTL_FARC_GET_RXSTATUS,
    NULL, 0,
    &rxStatus, sizeof(rxStatus),
    &read, &overlapped);

if (!ret)
{
   err = GetLastError();
   if (err == E_FARC_PENDING)
   {
      ret = GetOverlappedResult(drvhandle, &overlapped, &read, TRUE);
      if (!ret)
      {
         err = GetLastError();
         // do errorhandling here
      }
   }
   else
   {
      // other error occured, perhaps wrong handle
   }
}
if (rxStatus)
{
   // some unread packets available;
}
...

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