Creating cronjob in codeigniter on linux hosting server

// application/controllers/Company_controller.php
<?php
if(!defined('BASEPATH'))
    exit('No direct script access allowed');

class Company_controller extends CI_Controller {
    public function __construct() {
        parent::__construct();
        $this->load->model('companies_model');    
    }

// cron entry would be something like this:
// 1  1  *  *  *  /usr/bin/php [full path to]/index.php company_controller cronCLI AcmeCorp >/dev/null 2>&1
    public function cronCLI($firmName) {
        if(php_sapi_name() == 'cli') {
            $this->companies_model->doSomeDB_Process($firmName);
        } else {
            echo 'CLI only';
        }
    }
}

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
class Cron extends CI_Controller 
{
    /**
     * This is default constructor of the class
     */
    public function __construct()
    {
        parent::__construct();
        $this->load->library('input');
        $this->load->model('cron_model');
    }
    
    /**
     * This function is used to update the age of users automatically
     * This function is called by cron job once in a day at midnight 00:00
     */
    public function updateAge()
    {            
        // is_cli_request() is provided by default input library of codeigniter
        if($this->input->is_cli_request())
        {            
            $this->cron_model->updateAge();
        }
        else
        {
            echo "You dont have access";
        }
    }
}
?>