(PHP 5, PHP 7)
curl_multi_getcontent — Return the content of a cURL handle if CURLOPT_RETURNTRANSFER is set
$ch
   )
   If CURLOPT_RETURNTRANSFER is an option that is set for a specific handle, 
   then this function will return the content of that cURL handle in the form
   of a string.
  
   Return the content of a cURL handle if CURLOPT_RETURNTRANSFER is set.