The "test-smtp-send" command:

Usage: fossil test-smtp-send EMAIL FROM TO ...

Use SMTP to send the email message contained in the file named EMAIL
to the list of users TO.  FROM is the sender of the email.

Options:

     --direct              Go directly to the TO domain.  Bypass MX lookup
     --relayhost R         Use R as relay host directly for delivery.
     --port N              Use TCP port N instead of 25
     --trace               Show the SMTP conversation on the console