php guid

functionguid(){if(function_exists('com_create_guid')){returncom_create_guid();}else{mt_srand((double)microtime()*10000);$charid=strtoupper(md5(uniqid(rand(),true)));$hyphen=chr(45);$uuid=chr(123).substr($charid,0,8).$hyphen.substr($charid,8,4).$hyphen.substr($charid,12,4).$hyphen.substr($charid,16,4).$hyphen.substr($charid,20,12).chr(125);return$uuid;}}