php获取服务器端机器网卡的物理（MAC）地址

<?php
/**
获取机器网卡的物理（MAC）地址
wwa $Exp
**/
class GetMacAddr
{
var $return_array = array(); // 返回带有MAC地址的字串数组
var $mac_addr;

function GetMacAddr($os_type)
{
switch ( strtolower($os_type) )
{
case "linux":
$this->forLinux();
break;
case "solaris":
break;
case "unix":
break;
case "aix":
break;
default:
$this->forWindows();
break;
}

$temp_array = array();
foreach ( $this->return_array as $value )
{
if ( preg_match( "/[0-9a-f][0-9a-f][:-]"."[0-9a-f][0-9a-f][:-]"."[0-9a-f][0-9a-f][:-]"."[0-9a-f][0-9a-f][:-]"."[0-9a-f][0-9a-f][:-]"."[0-9a-f][0-9a-f]/i", $value, $temp_array ) )
{
$this->mac_addr = $temp_array[0];
break;
}
}
unset($temp_array);
return $this->mac_addr;
}

function forWindows()
{
@exec("ipconfig /all", $this->return_array);
if ( $this->return_array )
return $this->return_array;
else{
$ipconfig = $_SERVER["WINDIR"]."/system32/ipconfig.exe";
if ( is_file($ipconfig) )
@exec($ipconfig." /all", $this->return_array);
else
@exec($_SERVER["WINDIR"]."/system/ipconfig.exe /all", $this->return_array);
return $this->return_array;
}
}

function forLinux()
{
@exec("ifconfig -a", $this->return_array);
return $this->return_array;
}
}
?>
<?
$mac = new GetMacAddr(PHP_OS);
echo $mac->mac_addr;
?>