Get and Override Default Controller Programmatically

[eluser]goFrendiAsgard[/eluser]
Dear, everyone.

I know how to change the default controller by editing application/config/routes.php and changing this line

Code:

$route['default_controller'] = "Blog";

Now, I want to get the $route['default_controller'] value as string. Does anyone know how to do that?

Further I also want to change the $route['default_controller'] programmatically. I think I can do that by using file_put_contents in the risk of not permitted operation, so I still hope for better way to do it.

Thanks