, you may want to run a checkpoint before calling this
        method. To run a checkpoint, use the 
        <a class="xref" href="txncheckpoint.html" title="DB_ENV-&gt;txn_checkpoint()">DB_ENV-&gt;txn_checkpoint()</a>
        method. For more information on checkpoints, see
        <a href="../../programmer_reference/transapp_checkpoint.html" class="olink">Checkpoints</a> in the <em class="citetitle">Berkeley DB Programmer's Reference Guide</em>.
    </p>
      <p>
        To back up a single database file