PHP/codeigniter - use of exit()

In this case Pedro is correct. If they are not logged in just redirect them, it's even better if you can use Public/Admin named base controllers to stop you having to do this in each separate protected file.

Generally speaking though, if you use exit() it will stop the Output library for running. If you just want to stop the current controller from executing but allow output of the controller you can use return in exactly the same way.

function checkSession(){    return (bool) $this->session->userdata('is_logged_in');}

Then simply:

if(!$this->checkSession()){        //the session has expired!        $data['main'] = 'confirmation_message';        $data['title'] = "Session expired";        $this->load->vars($data);        $this->load->view('template');        return;}

exit() should only ever be used if you really want instant death of your application's execution for debugging, error reporting, etc.

In this case you should not use exit, what you should do if the session is not valid is redirect your app using example:

redirect('/init/login/','refresh');

I had a similar problem. Where I wanted to stop the user to due to no login. But I wanted to offer a list of links for them not simply redirect them to a login page. I am using CI version 1.7.2 and the $this->_output() $this->display->_output() and $this->output->_display() solutions did not work for me. I was however to get my results using the $this->output->get_output() function.

        $this->load->vars($data);        $this->load->view('template');        die($this->output->get_output());