$siReq->senderAddress = SENDER_ADDRESS;
$siReq->recipients = DESTINATION_ADDRESS;
$siReq->messageKey = SOCIAL_INVITES_MESSAGE_KEY;
# ----------------------------------------------------------------------------------------------------
# example:send-invite
$siResult = $socinv->sendInvite($siReq, API_KEY);
# ----------------------------------------------------------------------------------------------------
// The bulk id is a unique identifier of this api call:
$bulkId = $siResult->sendSmsResponse->bulkId;
# ----------------------------------------------------------------------------------------------------
$deliveryStatus = null;
if ($siResult != null) {
    for ($i = 0; $i < 4; $i++) {
        # example:query-for-delivery-status
        // You can use $bulkId as an method call argument here:
        $smsMessageStatus = $smsClient->queryDeliveryStatus($bulkId);
        echo "Getting status (try #", $i, "): \n<br />\n";
        for ($j = 0; $j < count($smsMessageStatus->deliveryInfo); $j++) {
            $deliveryStatus = $smsMessageStatus->deliveryInfo[$j]->deliveryStatus;
            echo 'Message[' . $j . '] => {', "\n";
            echo 'Success:', $smsMessageStatus->isSuccess() ? 'true' : 'false', "\n";
            echo 'Status:', $deliveryStatus, "\n";
            if (!$smsMessageStatus->isSuccess()) {
                echo 'Message id:', $smsMessageStatus->exception->messageId, "\n";
                echo 'Text:', $smsMessageStatus->exception->text, "\n";
                echo 'Variables:', $smsMessageStatus->exception->variables, "\n";
            }
            echo "\n} \n<br />\n";
        }
        echo "<br />";
        # ----------------------------------------------------------------------------------------------------