How to Get MAC Address of System using PHP

?php
   // Turn on output buffering
   ob_start();
   //Get the ipconfig details using system commond
   system('ipconfig /all');
   // Capture the output into a variable
   $mycomsys=ob_get_contents();
   // Clean (erase) the output buffer
   ob_clean();
   $find_mac = "Physical"; //find the "Physical" & Find the position of Physical text
   $pmac = strpos($mycomsys, $find_mac);
   // Get Physical Address
   $macaddress=substr($mycomsys,($pmac+36),17);
   //Display Mac Address
   echo $macaddress;

?>