Question about putting cookie information into URL parameter

We are trying to get the cookie information into the URL parameter. We are using this, but clearly this is not proper code.

<?php
header("Location: https://ourdomain.com/?c1=P1&flow=c...onv_s='+escape(convert.getCookie('_conv_s'));");
exit;
?>

How can we get the _conv_v and _conv_s cookie information into the url parameter?

I wouldn't use cookie ingo in the url. I would set up aphp session and save the cookie info in session variables. But if you want to change domains, I would do a POST request instead of adding the cookie info in the urls.

Read cookie with php and store it to a variable.
Then use javascript to load php variable and do what you want ..