e SQL standard, which is
        be <code class="literal">YYYY-MM-DD HH:MM:SS</code>.
       </p><p>
        Upon success, the function returns 0 and a negative value if an
        error occurred.
       </p></dd><dt id="ECPG-INFORMIX-FUNCTIONS-RFMTLONG"><span class="term"><code class="function">rfmtlong</code></span> <a href="#ECPG-INFORMIX-FUNCTIONS-RFMTLONG" class="id_link">#</a></dt><dd><p>
        Convert a long integer value to its textual representation using a
        format mask.
</p><pre class="sy