You could use a variable in session or cookie which
indicate if jettop is already started.
something like :
PHP Code:
session_start();
if(!isset($_SESSION['jettop_is_started'])) {
/* first lauch, jettop is not started yet */
/*...
code to start jettop
...
*/
$_SESSION['jettop_is_started'] = true;
}
if($I_want_stop_jettop_now) {
/* if you want to stop jettop */
`killall jettop`;
}