Pushing session data to a PHP file included via '<script>' -

i have small problem can't find exact solution to.

i have file called push.php grabs required information database, stores data via sessions , header redirect listing.php.

of course expect, listing.php able use session data , display info.

there external php file called in using <script type="text/javascript" src="map.api.php"></script> uses both js , php generate map. in map.api.php file not letting me echo session data (and yes, have started file session_start();)

how can post session data map.api.php without having reload page?

i think should use

include map.api.php; 

instead of

<script src="map.api.php"></script>