 seems inappropriate to put in the primary message.
     The message string is processed in just the same way as for
     <code class="function">errmsg</code>.
    </p></li><li class="listitem"><p>
     <code class="function">errdetail_internal(const char *msg, ...)</code> is the same
     as <code class="function">errdetail</code>, except that the message string will not be
     translated nor included in the internationalization message dictionary.
     This should be used for detail messages that are not