e>
                  (or the equivalent system error).
                </p></dd>
<dt><span class="term">ec</span></dt>
<dd><p>
                  Set to indicate what error occurred, if any. If the <code class="computeroutput"><span class="identifier">mode</span></code> is <code class="computeroutput"><span class="keyword">false</span></code>,
                  but the current value of <code class="computeroutput"><span class="identifier">non_blocking</span><span class="special">()</span></code> is <code cla