About cookies, sessions and the Remember Me box...

[coolegg]

I know a bit about cookies and sessions but I wonder if some of you could educate me about the details. The reason I ask is that I occasionally, but regularly, get emails from my members that they lose posts or edits to their profiles because they are prompted to log in after hitting the Submit button. (my member profiles are long, and can often take a long time to write) 95%+ of my members do not have problems like this, but some do.

First question... this sounds like a cookies issue right? The login/member cookie(s) are probably not being set for these members?

Second question... if a cookie is not set how long does the php Session variable last? How long before the member gets the log in screen again?

Third Question... If the Remember Me selection box on the login panel is NOT selected then no cookies will be set, is that right? So the member will see the same behaviour as if the cookies are blocked for them, is that right?

3B... What's wrong with forcing the Remember Me selection to ON by making it a hidden field? Are there disadvantages of doing that?

Fourth Question... I notice that many of the internal URLs in my templates have the variable $session[sessionurl] attached to the URL, so for example my Navbar template has the following link to one of my subforums: <A HREF="$vboptions[bburl]/forumdisplay.php?f=3&amp;$session[sessionurl]">

What is $session[sessionurl]? It is always blank in the Address line of my browser when surfing the site, is that normal?

So basically I am looking for a primer on cookies and sessions as it relates to vB.

Thanks in advance for any information.

- Drew