Implementation code for php curl to open URLs in batches (curl_multi class)

/*
 * After testing, curl_multi is faster than the Foreach loop when there are more than four URLs..
 * by wc1217
 * edit: bbs.it-home.org
 */
class curl_multi{
 //Curl handle
 //private $curl_handle = null;
 //Web address
 private $url_list = array();
 //Parameters
 private $curl_setopt = array(
 'CURLOPT_RETURNTRANSFER' => 1, / /The result is returned to the variable
 'CURLOPT_HEADER' => 0, //Do you want HTTP header?
 'CURLOPT_NOBODY' => 0, //No content?
 'CURLOPT_FOLLOWLOCATION' => 0, //Automatic tracking
 ' CURLOPT_TIMEOUT' => 6//Timeout(s)
 );

 function __construct($seconds = 30){
 set_time_limit($seconds);
 }

 /*
 * Set URL
 * @list array
 * /
 public function setUrlList($list = array()){
 $this->url_list = $list;
 }

 /*
 * Set parameters
 * @cutPot array
 */
 public function setOpt($cutPot ){
 $this->curl_setopt = $cutPot + $this->curl_setopt;
 }

 /*
 * Execute
 * @return array
 */
 public function exec(){
 $mh = curl_multi_init( );

 foreach($this->url_list as $i => $url){
 $conn[$i] = curl_init($url);

 foreach($this->curl_setopt as $key = > $val){
 curl_setopt($conn[$i], preg_replace('/(CURLOPT_w{1,})/ie', '$0', $key), $val);
 }
 curl_multi_add_handle($mh , $conn[$i]);
 }

 $active = false;

 do{
 $mrc ​​= curl_multi_exec($mh, $active);
 }while($mrc == CURLM_CALL_MULTI_PERFORM);

 while( $active and $mrc ​​== CURLM_OK){
 if(curl_multi_select($mh) != -1){
 do{
 $mrc ​​= curl_multi_exec($mh, $active);
 }while($mrc == CURLM_CALL_MULTI_PERFORM) ;
 }
 }

 $res = array();
 foreach($this->url_list as $i => $url){
 $res[$i] = curl_multi_getcontent($conn[$i]) ;
 curl_close($conn[$i]);
 curl_multi_remove_handle($mh, $conn[$i]); //Release resources immediately after use
 }
 curl_multi_close($mh);
 return $res;
 }
 }
?>