Accessing latest Betfair API through PHP

$user_agent = "Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)";
  
  $ch = curl_init();    // initialize curl handle
  curl_setopt($ch, CURLOPT_URL, API_URL ); // set url to post to
  curl_setopt($ch, CURLOPT_RETURNTRANSFER,1); // return into a variable
  curl_setopt($ch, CURLOPT_TIMEOUT, 60); // times out after 1 min
  curl_setopt($ch, CURLOPT_POSTFIELDS, $xml ); // add POST fields 
    
  curl_setopt($ch, CURLOPT_USERAGENT, $user_agent);
  
  $header[] = "SOAPAction: ". API_URL;
  $header[] = "MIME-Version: 1.0";
  $header[] = "Content-type: text/xml; charset=utf-8";  
  
  curl_setopt($ch, CURLOPT_HTTPHEADER, $header);
  $result = curl_exec($ch); // run the whole process  
  
  
  if (curl_errno($ch))
  {
   print curl_error($ch);
   return 0;
  }
  else
  {
   
   //now that we have got a result, parse this soap packet and return the XML doc
   $parser = new soap_parser($result,'UTF-8','',TRUE);
   $result = $parser->get_response();
   
   //print_R($result);
   curl_close($ch);
   
   if($result["Result"]["header"]["errorCode"] != "NO_SESSION" )
   {
    update_session_key($result["Result"]["header"]["sessionToken"] );
   }
   
   return $result;
  }