CSecuritySessionDB::write

static function write($id, $sessionData)
{
	if(!self::isValidId($id))
		return false;

	if (self::$isReadOnly)
	{
		if (!CSecuritySession::isOldSessionIdExist())
		{
			return true;
		}
	}

	if(CSecuritySession::isOldSessionIdExist())
		$oldSessionId = CSecuritySession::getOldSessionId(true);
	else
		$oldSessionId = $id;

	SessionTable::delete($oldSessionId);
	$result = SessionTable::add(array(
		'SESSION_ID' => $id,
		'TIMESTAMP_X' => new BitrixMainTypeDateTime,
		'SESSION_DATA' => base64_encode($sessionData),
	));

	return $result->isSuccess();
}