c.html">MDC</a> copy, if a value is found it is returned. Otherwise, if the search in <a class="el" href="classlog4cxx_1_1_m_d_c.html">MDC</a> copy returns an empty result, then the current thread's <code><a class="el" href="classlog4cxx_1_1_m_d_c.html">MDC</a></code> is used.<p>
Note that <em>both</em> the local <a class="el" href="classlog4cxx_1_1_m_d_c.html">MDC</a> copy and the current thread's <a class="el" href="classlog4cxx_1_1_m_d_c.html">MDC</a> are searched.  <dl compact><dt><b>Parameters:</b></dt