First off, I hope this is in the right area.
I'm writing a PHP script at the moment for a simple site which incorporates cookie-based logins. There is a "permanent login" function, for which a cookie is set, with a long lifetime.
My question is: is there a maximum lifetime for a cookie, and if so what is it?
If anyone knows the answer to this I'd be very grateful. I have tried 365 days so far, and that works fine.