An optional feature of email is a header that requests a return receipt once the recipient opened the email. You can add this header by using the otherhead$ template variable or email command/function parameter.


Call "",1,t$,e$$="some-email-address"

t.subject="test message"

t.otherhead$="Disposition-Notification-To: " + "return-to-email-address"

call "",0,t$,e$


Note that return receipts are requests, and the recipient is not required to honor the request.