ocks, regardless of <code>peer_socket-&gt;non_blocking()</code>. <code>write_some()</code> &ndash; if unable to immediately send 1+ bytes &ndash; will block until it can, if <code>peer_socket-&gt;non_blocking() == false</code> mode had been set. (That's why we named it <code>nb_...()</code>.)</li>
</ul>
<p >The following is not a concession, and these words may be redundant, but: <code>Peer_socket::write_some()</code> has 2 overloads; one that throws exception on error; and one that takes an <code>Error_cod