function
uuid(){
$chars = md5(uniqid(mt_rand(),
true
));
$uuid = substr($chars,0,8) .
'-'
;
$uuid .= substr($chars,8,4) .
'-'
;
$uuid .= substr($chars,12,4) .
'-'
;
$uuid .= substr($chars,16,4) .
'-'
;
$uuid .= substr($chars,20,12);
return
$uuid;
}