Generating url Link that expires after30 days!

[phpuser_2000]

Hi all!

I am trying to generate a url link that will expire after 30days or some days and it will also remmber the user based on the cookies and only that person froom the computer can download from that link.

Can anyone show me a sample code how to do that? Any links? example woudl be really helpfull

Thanks

[Installer]

How about some pseudocode?

if today minus date stored in cookie or database or elsewhere is less than 30 days
-and-
user has the correct cookie
then
show the link
else
don't show the link