fn main() {
    let resp = smtp_send(
        "127.0.0.1",
        2525,
        "tetherscript@example.test",
        ["alice@example.test", "bob@example.test"],
        "TetherScript SMTP smoke test",
        "hello from tetherscript\nthis message is DKIM-signed by default"
    )

    println("queued:", resp.code, resp.message)
}
