How to read in cookie if user is already logged on?

[bully]

I would like to extend my YabbSE with a special member-page and additional member info. Every member should be able to alter their own profile if already logged on.
So here the question:
How and where can I extract the user information from the YabbSE set cookie to determine the user's status?
Thx for answers...

[David]

Look in LogInOut.php and you will see how the cookie is set.

[bully]

Ah, I see, almost too easy  

Is there also a complete function somewhere which checks if the member is logged on before an action is executed?

Would be nice if I just could set an "if (function checkifloggedon()) { do my stuff }" and thats it.  

[Gobalopper]

Yes LoadCookie() does that already.

[bully]

so you are saying I can simply write:

if (LoadCookie()) {
  allow user xyz to change his stuff
}


or do I have to write:

LoadCookie();
if ($username != "Guest") {
     DO_MY_STUFF
}

because as far as I understand it, LoadCookie checks if the cookie is set, and if not it sets $username to "Guest".
That also explains the following SQL Select command with ...WHERE memberName=$username.

So my last version should be correct, shouldn't it?
Just checking the value of $username, and when it is "Guest" he is not registered.
Or other way round: I can allow member $username to access and change his profile ./profile/$username.php

Hope I got it now, thx for the help!

[[Unknown]]

Well, that would mean you would have a security risk.

Better, you should also LoadUserSettings() immediately after LoadCookie().  This will actually authenticate the user.

-[Unknown]

[bully]

... and thereby check if $username is in the database and retrieve his values to verify the first assumption that he really is $username.  

Smart thing to do, thx.

BTW: is there a good lecture on the internet about security issues in PHP and MySQL?
Seems like I have some more lessons to do on this