title: Read data into a circular buffer
body: <p>Is it possible to use <code>boost::circular_buffer</code> with <code>boost::asio</code>?</p>
  
  <p>Specifically I want to read a fixed number of bytes with <code>boost::asio::async_write</code> and store them directly in the circular buffer without copying. </p>
  
  <p>Some example code would be very nice!</p>