PHP Extension

Send an SMTP NOOP Command

Demonstrates the Chilkat MailMan.SmtpNoop method, which sends an SMTP NOOP command to the server. NOOP does nothing except elicit a positive response, which is useful for keeping a connection alive or verifying it is still responsive. This example opens an SMTP connection, sends a NOOP, and closes.

Background: When holding an SMTP connection open across many sends (see OpenSmtpConnection), an idle stretch can cause the server to time out and drop the socket. A periodic NOOP keeps the session active and confirms the server is still responding, so the next SendEmail doesn't fail on a silently-closed connection.

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PHP Extension

<?php

include("chilkat.php");

$success = false;

//  Demonstrates the MailMan.SmtpNoop method, which sends an SMTP NOOP command to the server.
//  NOOP does nothing except elicit a positive response, useful for keeping a connection
//  alive or verifying it is still responsive.

$mailman = new CkMailMan();

//  Configure the SMTP server connection.
$mailman->put_SmtpHost('smtp.example.com');
$mailman->put_SmtpPort(465);
$mailman->put_SmtpSsl(true);
$mailman->put_SmtpUsername('user@example.com');
$mailman->put_SmtpPassword('myPassword');

//  Open the SMTP connection.

$success = $mailman->OpenSmtpConnection();
if ($success == false) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

//  Send a NOOP to keep the connection alive.
$success = $mailman->SmtpNoop();
if ($success == false) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

$success = $mailman->CloseSmtpConnection();
if ($success == false) {
    print $mailman->lastErrorText() . "\n";
    exit;
}

print 'SMTP NOOP succeeded.' . "\n";

?>