What resources or documentation can be helpful for understanding PHP functions related to managing user sessions and online status?

To manage user sessions and online status in PHP, it is helpful to understand functions such as session_start(), session_destroy(), and session_unset(). These functions allow you to start, destroy, and unset session variables, respectively. You can use these functions to track and manage user sessions, including their online status.

// Start session
session_start();

// Set user as online
$_SESSION['online_status'] = true;

// Check if user is online
if(isset($_SESSION['online_status']) && $_SESSION['online_status'] == true) {
    echo 'User is online';
}

// Destroy session
session_destroy();