computeroutput">buffer_size(cb) == 0</code>, the operation
                  completes immediately. <code class="computeroutput">ec</code> is set such that <code class="computeroutput">!ec</code>
                  is <code class="computeroutput">true</code>, and <code class="computeroutput">n</code> is 0.
                </p>
              </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break">
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
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