How to tell when somone leaves?

[Anon]

Most of us know how to get the IP address of someone that is visiting our web site:

$ip = getenv("REMOTE_ADDR");

But does anyone know of a way to tell when that person has left the web site? I would like to know just how much time a person spends on one of my web pages. Does the PHP library have any function that will do this?

Or, is there another method to track this parameter (cookies, sessions, etc.) that could work?

[Anon]

There is no way to tell exactly when somebody leaves your website. You can manage a guess as to how long they were at your website by recording their arrival time, and then recording the last time they visit a page on your website, then guess an approximate ammount of time they spent there.

And this isn't just a PHP issue... you can not do this with any web-based software. This is because it is stateless, and people are only connected to your server until they finish downloading the files they need. Then they are officialy gone until their next visit.

Hope this helps,
-Josh B

[Anon]

you can do this in ASP, save a cookie, then access it on all the other pages, then you can save a fileon your server name their IP minus the .s and then save in the file the ending time minus the starting time (first put them into second format) and close the file. Tada!

[[deleted]]

"I would like to know just how much time a person spends on one of my web pages."

This is a standard function of nearly every webserver log analyzer, you don't need (want) to do this with PHP.