Function Problem

I'm having a problem with a php application; I have two files: one is ccadduser wich adds users to a controlcenter that I am currently designing for a website. In that ccaduserfile I call for a function checkpermission(); this function is defined in another file called ccfunctions When a user does not have access to the script it should abort the script, this is done using a header("location: ccnopermission.php"); statement But now it seems that while executing the function checkpermission() the code in ccadduser just keeps running and the database query that inserts the new user is executed before the user can be redirected to ccnopermission. Is there a way to make php wait until checkpermission is completely executed? I know it is not a simple question, but I really need a solution to ensure the safety of my system. grtz & thanks DragonEye