php的file_get_contents和curl差距

function curl_get_contents($durl){  $ch = curl_init();  curl_setopt($ch, CURLOPT_URL, $durl);  curl_setopt($ch, CURLOPT_TIMEOUT, 5);  curl_setopt($ch, CURLOPT_USERAGENT, _USERAGENT_);  curl_setopt($ch, CURLOPT_REFERER,_REFERER_);  curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);  $r = curl_exec($ch);  curl_close($ch);   return $r;}

用这个函数curl_get_contents代替file_get_contents