PHP Inform

Get MAC address in PHP

<?PHP 
$ip = getenv ( "REMOTE_ADDR" ); 
$matches =array(); 
if ( PHP_OS == 'WINNT' ) 
{ 
exec ( "arp -a" , $rgResult ); 
$mac_template = "/[\d|A-F]{2}\-[ \d|A-F]{2}\-[\d|A-F]{2}\-[\d| A-F]{2}\-[\d|A-F]{2}\-[\d|A-F] {2}/i" ; 
foreach( $rgResult as $key => $value ) 
{ 
if ( strpos ( $value , $ip )!== FALSE ) 
{ 
preg_match ( $mac_template , $value , $matches ); 
break; 
} 
}; 
} 
else 
{ 
exec ( "arp -a | grep $ip" , $rgResult ); 
$mac_template = "/[\d|A-F]{2}\:[ \d|A-F]{2}\:[\d|A-F]{2}\:[\d| A-F]{2}\:[\d|A-F]{2}\:[\d|A-F] {2}/i" ; 
preg_match ( $mac_template , $rgResult [ 0 ], $matches ); 
} 
$mac = $matches [ 0 ];
?>