mta_log
static void mta_log(const struct mta_envelope *, const char *, const char *,
mta_log(e, "Ok", source, relay, status);
mta_log(e, "TempFail", source, relay, status);
mta_log(e, "PermFail", source, relay, status);
mta_log(e, "PermFail", source, relay, "Loop detected");