How to read (get) cookie expiry value?

Make sure when testing, all cookies are cleared. The expiry will appear in the server response that initially sets the cookie, but should not be in subsequent responses. Make sure in the testing, that particular response is being captured.

I am able to get this to work on a test page with the following:

 when HTTP_RESPONSE {
 if {[HTTP::cookie exists "NID"] } {
    set expires [HTTP::cookie expires "NID"]
    log local0. "$expires"
   }
 }

Log output: