Session expire and destroy other sessions

session_helpers.php

<?php

const SESSION_EXPIRATION_TIME = 100; // Seconds
function session_expire()
{
    if (empty($_SESSION['last_visit'])) {
        $_SESSION['last_visit'] = time();
    }

    if ($_SESSION['last_visit'] + SESSION_EXPIRATION_TIME < time()) {

        session_destroy();
        session_write_close();

        session_start();
        session_regenerate_id(true);
    }
}

function session_destroy_id($id)
{
    // Close current session
    $current_session_id = session_id();
    session_write_close();

    // Start session that we need to destroy
    session_id($id);
    session_start();
    session_destroy();
    session_write_close();

    // Re-Start current session
    session_id($current_session_id);
    session_start();
}