title: what happens when recv() called with null buffer
body: <p>I'm curious to know what happens when below call is made .</p>
  
  <pre><code>recv(&lt;socket no&gt;, NULL , &lt;lenght&gt; , 0) ;
  </code></pre>
  
  <p>and also one more question is that , after calling recv function data on socket gets flushed or what happens really ?</p>
  
  <p>Regards,
  Kiran</p>