umask(0);
Mage::App()->loadArea('admin');
Mage::getSingleton('core/session', array('name'=>'adminhtml'));
$buffer = 'SOME STRING OR CSV CONTENT OR WHATEVER';
file_put_contents('media/cj_export.csv',$buffer);

$adapter=Mage::getSingleton('imagecdn/adapter_amazons3');
$adapter->save('/cj_export.csv','media/cj_export.csv');