SMTP has a SEND command, so it should use that for such a purpose, I should think. But of course, not all email services support it, but you can use MAIL instea

SMTP has a SEND command, so it should use that for such a purpose, I should think. But of course, not all email services support it, but you can use MAIL instead of SEND is not recognized, and then it will still work. I usually receive a notification in the status bar on my computer as soon as the message is sent, although that is because I run my own email server. If you use someone else's server, then such a thing is more difficult, and may be too slow.