Where do I put the URL?

I have changed all the code in the login.php
But I just don't get it. Where do I put my own redirection link? Or did I misunderstand this thing?

What I want to do is when people logout from my phpbb forum they should end up in my index.php outside the phpbb folder.
Maybe I din't need this? Maybe it's something simple to put somewhere else?

Pleeeease help... a newbie.

The redirection URL has to be placed in the logout link. This is explained a little in redirect_outside.txt.

The only thing I found there was this:

# Once all these modifications have been applied, you can use log in forms to
# redirect users outside the phpBB directories by adding two hidden form inputs
# like these:
# <input type="hidden" name="outside" value="1" />
# <input type="hidden" name="redirect" value="index.htm" />
# You can also create log in links like this one:
# <a href="login.php?redirect=/index.html&outside=1">Log In</a>
# And you can create log out links like this one:
# <a href="login.php?logout=true&redirect=/index.phtml&outside=1">Log Out</a>


But where should I put that in the codes of the phpbb?
Where is the actual logout URL to be placed?

Since I have a navigation in the header that have profile, FAQ, memberlist, logout and so on.
I want my logout action to use that one from the regular navigation in the top.
So when my visitors leave the forum, they should end up in my main page instead.
Which is in the root index.php

But I just don't know where to look for that logout and how to change it...