      <code class="literal">ECPG_INFORMIX_BAD_MONTH</code> - The input string does not
           contain a valid month.
          </p></li><li class="listitem"><p>
           <code class="literal">ECPG_INFORMIX_BAD_YEAR</code> - The input string does not
           contain a valid year.
          </p></li></ul></div><p>
       </p><p>
        Internally this function is implemented to use the <a class="xref" href="ecpg-pgtypes.html#PGTYPESDATEDEFMTASC"><code class="function">PGTYPESdate_defmt_asc</code></a