php 获取mac地址

<?php 
/**  
* 获取机器网卡的物理（MAC）地址
* 目前支持WIN/LINUX系统  
* 编辑: www.jbxue.com
**/ 
class MacAddInfo {     
    var $return_array = array (); // 返回带有MAC地址的字串数组   
    var $mac_addr; 
     
    function MacAddInfo($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"] . "system32ipconfig.exe"; 
            if (is_file ( $ipconfig )) 
                @exec ( $ipconfig . " /all", $this->return_array ); 
            else 
                @exec ( $_SERVER ["WINDIR"] . "systemipconfig.exe /all", $this->return_array ); 
            return $this->return_array; 
        } 
    } 

 function forLinux() { 
        @exec ( "ifconfig -a", $this->return_array ); 
        return $this->return_array; 
    } 
} 
//调用示例
//$mac = new MacAddInfo(PHP_OS);   
//echo $mac->mac_addr;   
?>