Session variables (was: [thelist] Pop-up when user leaves sit e.)

[Scott Dexter]

> |
> | Those web pages that say "There are currently 44 people visiting our
> | websites"? The webmasters are likely to lie about other 
> things as well.

How is this a lie?

If I have a log entry that you grabbed my default.asp page twenty seconds
ago, I can reasonably say that you are currently visiting my site. I can
also consider the current simultaneous connections open --remember there is
something called HTTP Keep-Alives, which, when negotiated (it's http 1.1),
keeps the connection from the browser to the webserver open. This makes
grabbing supplemental files (images, css files, etc) faster.

Statistics programs typically employ algorithms that consider how recently
pages were viewed by individual ip addresses to come up with a "44 people
are visiting" number.

Server-side engines (ASP, CF) *can* use their own Session tracking (not sure
of the analogous CF term) to display this, but it can be erroneous for a
couple reasons: bad implementation (the site developer has to write stuff,
at least in ASP anyway), idle sessions (you set your session timeout for 20
minutes, and it lives for the full 20 minutes even though I was there only
5), and in the case of ASP, bugs (the Session_OnEnd event does not fire, so
you can't do reliable cleanup/accounting).

So it's not a lie, but a close estimate based on real numbers. If you ask my
opinion on using "44 people are visiting my site right now,"  on a page, I'd
say it's a good exercise, but not something to require/push as a necessary
item (IOW, who cares how many people are visiting the site, except the site
owner(s)?)

forgive me if this is redundant/off-base; I missed most of the thread....

sgd