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<div class="titlepage"><div><div><h4 class="title">
<a name="boost_asio.reference.connect.overload8"></a><a class="link" href="overload8.html" title="connect (8 of 12 overloads)">connect (8
        of 12 overloads)</a>
</h4></div></div></div>
<p>
          Establishes a socket connection by trying each endpoint in a sequence.
        </p>
<pre class="programlisting">template&lt;
    typename <a class="link" href="../Protocol.html" title="Protocol requirements">Protocol</a>,
    typename <a class="link" href="../Executor1.html" title="Executor requirements">Executor</a>,
    typename <a class="link" href="../EndpointSequence.html" title="Endpoint sequence requirements">EndpointSequence</a>,
    typename <a class="link" href="../ConnectCondition.html" title="Connect condition requirements">ConnectCondition</a>&gt;
Protocol::endpoint connect(
    basic_socket&lt; Protocol, Executor &gt; &amp; s,
    const EndpointSequence &amp; endpoints,
    ConnectCondition connect_condition,
    boost::system::error_code &amp; ec,
    typename enable_if&lt; is_endpoint_sequence&lt; EndpointSequence &gt;::value &gt;::type *  = 0);
</pre>
<p>
          This function attempts to connect a socket to one of a sequence of endpoints.
          It does this by repeated calls to the socket's <code class="computeroutput">connect</code> member
          function, once for each endpoint in the sequence, until a connection is
          successfully established.
        </p>
<h6>
<a name="boost_asio.reference.connect.overload8.h0"></a>
          <span class="phrase"><a name="boost_asio.reference.connect.overload8.parameters"></a></span><a class="link" href="overload8.html#boost_asio.reference.connect.overload8.parameters">Parameters</a>
        </h6>
<div class="variablelist">
<p class="title"><b></b></p>
<dl class="variablelist">
<dt><span class="term">s</span></dt>
<dd><p>
                The socket to be connected. If the socket is already open, it will
                be closed.
              </p></dd>
<dt><span class="term">endpoints</span></dt>
<dd><p>
                A sequence of endpoints.
              </p></dd>
<dt><span class="term">connect_condition</span></dt>
<dd>
<p>
                A function object that is called prior to each connection attempt.
                The signature of the function object must be:
</p>
<pre class="programlisting">bool connect_condition(
    const boost::system::error_code&amp; ec,
    const typename Protocol::endpoint&amp; next);
</pre>
<p>
                The <code class="computeroutput">ec</code> parameter contains the result from the most recent
                connect operation. Before the first connection attempt, <code class="computeroutput">ec</code>
                is always set to indicate success. The <code class="computeroutput">next</code> parameter
                is the next endpoint to be tried. The function object should return
                true if the next endpoint should be tried, and false if it should
                be skipped.
              </p>
</dd>
<dt><span class="term">ec</span></dt>
<dd><p>
                Set to indicate what error occurred, if any. If the sequence is empty,
                set to <code class="computeroutput">boost::asio::error::not_found</code>. Otherwise, contains
                the error from the last connection attempt.
              </p></dd>
</dl>
</div>
<h6>
<a name="boost_asio.reference.connect.overload8.h1"></a>
          <span class="phrase"><a name="boost_asio.reference.connect.overload8.return_value"></a></span><a class="link" href="overload8.html#boost_asio.reference.connect.overload8.return_value">Return Value</a>
        </h6>
<p>
          On success, the successfully connected endpoint. Otherwise, a default-constructed
          endpoint.
        </p>
<h6>
<a name="boost_asio.reference.connect.overload8.h2"></a>
          <span class="phrase"><a name="boost_asio.reference.connect.overload8.example"></a></span><a class="link" href="overload8.html#boost_asio.reference.connect.overload8.example">Example</a>
        </h6>
<p>
          The following connect condition function object can be used to output information
          about the individual connection attempts:
        </p>
<pre class="programlisting">struct my_connect_condition
{
  bool operator()(
      const boost::system::error_code&amp; ec,
      const::tcp::endpoint&amp; next)
  {
    if (ec) std::cout &lt;&lt; "Error: " &lt;&lt; ec.message() &lt;&lt; std::endl;
    std::cout &lt;&lt; "Trying: " &lt;&lt; next &lt;&lt; std::endl;
    return true;
  }
};
</pre>
<p>
          It would be used with the <code class="computeroutput">boost::asio::connect</code> function as
          follows:
        </p>
<pre class="programlisting">tcp::resolver r(my_context);
tcp::resolver::query q("host", "service");
tcp::socket s(my_context);
boost::system::error_code ec;
tcp::endpoint e = boost::asio::connect(s,
    r.resolve(q), my_connect_condition(), ec);
if (ec)
{
  // An error occurred.
}
else
{
  std::cout &lt;&lt; "Connected to: " &lt;&lt; e &lt;&lt; std::endl;
}
</pre>
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      Kohlhoff<p>
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