title: Issue with CURL POST request, getting curl_setopt() parameter warning
body: <p>Tried to send the post request with XML body using CURL but constantly getting following error,</p>
  
  <pre><code>Warning: curl_setopt() expects parameter 2 to be long, string given
  </code></pre>
  
  <p>I'm using following CURL request,</p>
  
  <pre><code>$ch = curl_init(POST_URL);
  
  curl_setopt($ch, CURLOPT_MUTE, 1);
  curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 1);
  curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 1);
  curl_setopt($ch, CURLOPT_POST, 1);
  curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: text/xml'));
  curl_setopt($ch, CURLOPT_POSTFIELDS, "$xml");
  curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
  
  $output = curl_exec($ch);
  curl_close($ch);
  </code></pre>