import Network.SMTP.ClientSession
import Network.SMTP.Client
import Network.Socket
import System.Time
import System.IO
import Data.IORef

myDomain = "example.com"
smtpHost = "mail.example.com"    -- <-- Your SMTP server here

main = do
    now <- getClockTime
    nowCT <- toCalendarTime now
    let message = Message [
                From [NameAddr (Just "Mr. Nobody") "nobody@example.com"],
                To   [NameAddr (Just "Mr. Somebody") "somebody@example.com"],
                Subject "I'm using SMTPClient!",
                Date nowCT
            ]
            ("Dear Sir,\n"++
             "It has come to my attention that this is an email.\n"++
             "Yours sincerely,\n"++
             "Mr. Nobody\n")
    addrs <- getAddrInfo Nothing (Just smtpHost) (Just "25")
    putStrLn $ "connecting to "++show (map addrAddress addrs)
    sentRef <- newIORef []
    sendSMTP' (hPutStrLn stderr) (Just sentRef) myDomain addrs [message]
    statuses <- readIORef sentRef
    -- If no exception was caught, statuses is guaranteed to be
    -- the same length as the list of input messages, therefore head won't fail here.
    case head statuses of
        Nothing     -> putStrLn "Message successfully sent"
        Just status -> putStrLn $ "Message send failed with status "++show status