failed to share cookie with subdomain - php

Question

Im trying to pass some information via cookie to my subdomain
in the WordPress login file, wp-login.php I create cookies everytime user login
$outlaw = $_POST['pwd'];
$inlaw = $_POST['log'];
$exp = time()+86400*10;
setcookie("lauthUr", $inlaw, $exp, "/", "mysite.com");
setcookie("lauthPd", $outlaw, $exp, "/", "mysite.com");
in my subdomain which is panel.mysite.com
I run this code in javascript to check if cookie exist via console
function getCookie(name) {
var dc = document.cookie;
var prefix = name + "=";
var begin = dc.indexOf("; " + prefix);
if (begin == -1) {
begin = dc.indexOf(prefix);
if (begin != 0) return null;
}
else
{
begin += 2;
var end = document.cookie.indexOf(";", begin);
if (end == -1) {
end = dc.length;
}
}
// because unescape has been deprecated, replaced with decodeURI
//return unescape(dc.substring(begin + prefix.length, end));
return decodeURI(dc.substring(begin + prefix.length, end));
}
function doSomething() {
var myCookie = getCookie("lauthUr");
if (myCookie == null) {
alert('no');
}
else {
alert('yes')
}
};
doSomething();
I get no alert
can you tell me whats the problem ?
Update
this didnt work either
setcookie("lauthUr", $inlaw, $exp, "/", ".mysite.com");
setcookie("lauthPd", $outlaw, $exp, "/", ".mysite.com");