(PHP 5 >= 5.4.0, PHP 7)
Write session data
abstract public bool SessionHandlerInterface::write ( string $session_id, string $session_data )
Writes the session data to the session storage. Called by session_write_close(), when session_register_shutdown() fails, or during a normal shutdown. Note: SessionHandlerInterface::close() is called immediately after this function.
PHP will call this method when the session is ready