AbstractSessionHandler::close

public function close(): bool
{
	if (!$this->readOnly && $this->validateSessionId($this->sessionId))
	{
		if (isSessionExpired())
		{
			$this->destroy($this->sessionId);
		}

		if ($this->releaseLockAfterClose)
		{
			$this->unlock($this->sessionId);
		}

		$this->releaseLocksAfterValidate();
	}

	$this->sessionId = null;
	$this->lastCreatedId = null;

	return true;
}