Unicode C

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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Unicode C

#include <C_CkMailManW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkMailManW mailman;

    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 = CkMailManW_Create();

    //  Configure the SMTP server connection.
    CkMailManW_putSmtpHost(mailman,L"smtp.example.com");
    CkMailManW_putSmtpPort(mailman,465);
    CkMailManW_putSmtpSsl(mailman,TRUE);
    CkMailManW_putSmtpUsername(mailman,L"user@example.com");
    CkMailManW_putSmtpPassword(mailman,L"myPassword");

    //  Open the SMTP connection.

    success = CkMailManW_OpenSmtpConnection(mailman);
    if (success == FALSE) {
        wprintf(L"%s\n",CkMailManW_lastErrorText(mailman));
        CkMailManW_Dispose(mailman);
        return;
    }

    //  Send a NOOP to keep the connection alive.
    success = CkMailManW_SmtpNoop(mailman);
    if (success == FALSE) {
        wprintf(L"%s\n",CkMailManW_lastErrorText(mailman));
        CkMailManW_Dispose(mailman);
        return;
    }

    success = CkMailManW_CloseSmtpConnection(mailman);
    if (success == FALSE) {
        wprintf(L"%s\n",CkMailManW_lastErrorText(mailman));
        CkMailManW_Dispose(mailman);
        return;
    }

    wprintf(L"SMTP NOOP succeeded.\n");


    CkMailManW_Dispose(mailman);

    }