help with customers logged on or not

[devilgrins]

how do i write the code to check if the customer is logged on.. to display a hello <customer name> else a hello guest, please click to register or login..

 

 

i just want a simple check to see if its a guest or customer.. and if so certain things would show differently.

[Guest]

here is an example

  if (tep_session_is_registered('customer_id')) {
//here we execute something because the customer is logged in
 } else {
// else ask him to login
tep_redirect(tep_href_link(FILENAME_LOGIN, '', 'SSL'));
}