uteroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">uint64_t</span></code>
                </p>
              </td>
<td>
                <p>
                  This static member function is optional. It returns the payload
                  size of <code class="computeroutput"><span class="identifier">body</span></code> in
                  bytes not including any chunked transfer encoding. The return value
                  may be zero, to indicate that th