Setting session cookie

[Wizardjv]

Ok say I have this cookie for example

(this is example cookie from Firefox)
name:user
Content:123456-%64%69%72%74%79%73%70%61%63%65%77
Domain:.domain.com
Path: /
Send For:any type of connection
Expires: when browser is closed

I wanna know exactly what code I would need to use to set that cookie. Like the set cookie code that would equal that output.. I have been trying to get it to work but it doesnt.

here is what I thought should work

<?php

setcookie('user', '123456-%64%69%72%74%79%73%70%61%63%65%77', false , '/', '.domain.com', 0);

?>

But it doesnt set the cookie... If someone could point me in right direction or tell me what im doing wrong I would greatly appreciate it... Thank you in advance