Send File by Email through Form on Web Site?

Code:
function apply(){

  

    $slug = $this->input->post('slug');

  

    $data['page_data'] = $this->MPages->getPageBySlug('vacancies');

    //$data['page_data'] = $this->MVacancies->getVacancyItem($slug);

    //$data['page_data'] or redirect('vacancies/');

    

    $data['title'] = $data['page_data']['title'];

    $data['body'] = $data['page_data']['body'];

    

      if(isset($_FILES['file']['name'])) {

      

              $email = '[email protected]';

              

        $file_name = $this->do_upload(); // _do_upload() should return the path and name of the uploaded file

        $this->email->attach($file_name);

        

              $message = "$email has applied for this job.";

              $this->email->from($email, '[email protected]');

              $this->email->to('[email protected]');

              

              $this->email->subject('Application for Job #' . $id);

              $this->email->message($message);

              

              $this->email->send();

              

              $this->load->view('form_success');

              

          } else {

          

        $data['main'] = 'vacancies_apply';

        $this->load->vars($data);    

        $this->load->view('template');

        

      }

    

  }

  

  function do_upload()

    {

        $config['upload_path'] = './uploads/';

        $config['allowed_types'] = 'gif|jpg|png';

        $config['max_size']    = '100';

        $config['max_width']  = '1024';

        $config['max_height']  = '768';

        

        $this->load->library('upload', $config);

    

        if ( ! $this->upload->do_upload())

        {

            $error = array('error' => $this->upload->display_errors());

            

            $this->load->view('upload_form', $error);

        }    

        else

        {

            $data = array('upload_data' => $this->upload->data());

            

            $this->load->view('upload_success', $data);

        }

    }