receive data from autoloading file

[eluser]mohfeza code ignitor[/eluser]
please let me know ASAP how to receive data from autoloading file?

I created a file in application/config/ folder named amazonconfig.php
and autoloaded it in application/config/autoload.php as

$autoload['config']=array('amazonconfig');

amazonconfig contains $config['aid']='php9webcom9';

I tried to get data using echo $aid; but not working.
Please let me know if you have any solution.