Validated user?

[eluser]Unknown[/eluser]
http://pastie.org/2321229

Above is a link which shows you what I had on my old version of my website where the user logged in and it welcomed them to the site again.

The code given in the pastie link is something I understand but im finding it troublesome trying to convert it into a way for codeigniter to use.

Can someone assist me with how to do this?

Thanks