title: How to determine how much of the socket receive buffer is filled?
body: <p>In my application, I am trying to send and receive datagrams to different servers as quickly as possible.  I noticed that increasing the sending rate is greatly lowering the percentage of responses I receive for a given # of sends.  I believe one cause could be recvfrom()'s queue is filling faster than I can call the function to read the packets, reaching the end and dropping a a lot of packets.  Is there a way I can check how full the receive buffer is for a socket?</p>
  
  <p>This is on Windows, not Linux, and I would prefer a programmatic approach.</p>