SharedMailboxesManager::getUserIdsWithAccessToMailbox

static function getUserIdsWithAccessToMailbox($mailboxId)
{
	$userCodes = MailboxAccessTable::query()
		->addSelect('ACCESS_CODE')
		->where('MAILBOX_ID', $mailboxId)
		->whereLike('ACCESS_CODE', 'U%')
		->exec()
		->fetchAll();
	$results = [];
	foreach ($userCodes as $userAccessCode)
	{
		// @TODO: departments
		if (preg_match('#U[0-9]+#', $userAccessCode['ACCESS_CODE']) === 1)
		{
			$results[] = mb_substr($userAccessCode['ACCESS_CODE'], 1);
		}
	}
	return $results;
}