code: public function getInfo(int $opt):string {
  		if($opt <= 0) {
  			throw new CurlException(
  				"Option must be greater than zero, "
  				. $opt
  				. " given."
  			);
  		}
  		return curl_getinfo($this->ch, $opt);
  	}
docs: Get information regarding the transfer
  @see http://php.net/manual/en/function.curl-getinfo.php