How can session_start() be properly utilized in PHP to avoid errors related to undefined variables like $_SESSION?

When using session_start() in PHP, it is important to ensure that the $_SESSION superglobal array is initialized to avoid errors related to undefined variables. One way to do this is by checking if the session has already started before accessing or setting any session variables. This can be done by using session_status() function to check if the session is active before calling session_start().

if (session_status() == PHP_SESSION_NONE) {
    session_start();
}