Tcl

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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Tcl


load ./chilkat.dll

set success 0

#  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.

set mailman [new_CkMailMan]

#  Configure the SMTP server connection.
CkMailMan_put_SmtpHost $mailman "smtp.example.com"
CkMailMan_put_SmtpPort $mailman 465
CkMailMan_put_SmtpSsl $mailman 1
CkMailMan_put_SmtpUsername $mailman "user@example.com"
CkMailMan_put_SmtpPassword $mailman "myPassword"

#  Open the SMTP connection.

set success [CkMailMan_OpenSmtpConnection $mailman]
if {$success == 0} then {
    puts [CkMailMan_lastErrorText $mailman]
    delete_CkMailMan $mailman
    exit
}

#  Send a NOOP to keep the connection alive.
set success [CkMailMan_SmtpNoop $mailman]
if {$success == 0} then {
    puts [CkMailMan_lastErrorText $mailman]
    delete_CkMailMan $mailman
    exit
}

set success [CkMailMan_CloseSmtpConnection $mailman]
if {$success == 0} then {
    puts [CkMailMan_lastErrorText $mailman]
    delete_CkMailMan $mailman
    exit
}

puts "SMTP NOOP succeeded."

delete_CkMailMan $mailman