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  26 <div class="titlepage"><div><div><h6 class="title">
  27 <a name="beast.ref.boost__beast__basic_stream.async_connect.overload2"></a><a class="link" href="overload2.html" title="basic_stream::async_connect (2 of 5 overloads)">basic_stream::async_connect
  28           (2 of 5 overloads)</a>
  29 </h6></div></div></div>
  30 <p>
  31             Establishes a connection by trying each endpoint in a sequence asynchronously.
  32           </p>
  33 <h7><a name="beast.ref.boost__beast__basic_stream.async_connect.overload2.h0"></a>
  34             <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.async_connect.overload2.synopsis"></a></span><a class="link" href="overload2.html#beast.ref.boost__beast__basic_stream.async_connect.overload2.synopsis">Synopsis</a>
  35           </h7><pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
  36     <span class="keyword">class</span> <a href="../../../../../../../../doc/html/boost_asio/reference/EndpointSequence.html" target="_top"><span class="emphasis"><em>EndpointSequence</em></span></a><span class="special">,</span>
  37     <span class="keyword">class</span> <a href="../../../../../../../../doc/html/boost_asio/reference/RangeConnectHandler.html" target="_top"><span class="emphasis"><em>RangeConnectHandler</em></span></a> <span class="special">=</span> <span class="identifier">net</span><span class="special">::</span><span class="identifier">default_completion_token_t</span><span class="special">&lt;</span><span class="identifier">executor_type</span><span class="special">&gt;&gt;</span>
  38 <a href="../../../../../../../../doc/html/boost_asio/reference/asynchronous_operations.html#boost_asio.reference.asynchronous_operations.automatic_deduction_of_initiating_function_return_type" target="_top"><span class="emphasis"><em>DEDUCED</em></span></a>
  39 <span class="identifier">async_connect</span><span class="special">(</span>
  40     <span class="identifier">EndpointSequence</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">endpoints</span><span class="special">,</span>
  41     <span class="identifier">RangeConnectHandler</span><span class="special">&amp;&amp;</span> <span class="identifier">handler</span> <span class="special">=</span> <span class="identifier">net</span><span class="special">::</span><span class="identifier">default_completion_token_t</span><span class="special">&lt;</span> <span class="identifier">executor_type</span> <span class="special">&gt;{});</span>
  42 </pre>
  43 <h7><a name="beast.ref.boost__beast__basic_stream.async_connect.overload2.h1"></a>
  44             <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.async_connect.overload2.description"></a></span><a class="link" href="overload2.html#beast.ref.boost__beast__basic_stream.async_connect.overload2.description">Description</a>
  45           </h7><p>
  46             This function attempts to connect the stream to one of a sequence of
  47             endpoints by trying each endpoint until a connection is successfully
  48             established. The underlying socket is automatically opened if needed.
  49             An automatically opened socket is not returned to the closed state upon
  50             failure. The algorithm, known as a <span class="emphasis"><em>composed asynchronous operation</em></span>,
  51             is implemented in terms of calls to the underlying socket's <code class="computeroutput"><span class="identifier">async_connect</span></code> function. If the timeout
  52             timer expires while the operation is outstanding, the current connection
  53             attempt will be canceled and the completion handler will be invoked with
  54             the error <a class="link" href="../../boost__beast__error.html" title="error"><code class="computeroutput"><span class="identifier">timeout</span></code></a>.
  55           </p>
  56 <h7><a name="beast.ref.boost__beast__basic_stream.async_connect.overload2.h2"></a>
  57             <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.async_connect.overload2.parameters"></a></span><a class="link" href="overload2.html#beast.ref.boost__beast__basic_stream.async_connect.overload2.parameters">Parameters</a>
  58           </h7><div class="informaltable"><table class="table">
  59 <colgroup>
  60 <col>
  61 <col>
  62 </colgroup>
  63 <thead><tr>
  64 <th>
  65                     <p>
  66                       Name
  67                     </p>
  68                   </th>
  69 <th>
  70                     <p>
  71                       Description
  72                     </p>
  73                   </th>
  74 </tr></thead>
  75 <tbody>
  76 <tr>
  77 <td>
  78                     <p>
  79                       <code class="computeroutput"><span class="identifier">endpoints</span></code>
  80                     </p>
  81                   </td>
  82 <td>
  83                     <p>
  84                       A sequence of endpoints. This this object must meet the requirements
  85                       of <span class="emphasis"><em>EndpointSequence</em></span>.
  86                     </p>
  87                   </td>
  88 </tr>
  89 <tr>
  90 <td>
  91                     <p>
  92                       <code class="computeroutput"><span class="identifier">handler</span></code>
  93                     </p>
  94                   </td>
  95 <td>
  96                     <p>
  97                       The completion handler to invoke when the operation completes.
  98                       The implementation takes ownership of the handler by performing
  99                       a decay-copy. The equivalent function signature of the handler
 100                       must be:
 101                     </p>
 102 <pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="keyword">void</span> <span class="identifier">handler</span><span class="special">(</span>
 103     <span class="comment">// Result of operation. if the sequence is empty, set to</span>
 104     <span class="comment">// net::error::not_found. Otherwise, contains the</span>
 105     <span class="comment">// error from the last connection attempt.</span>
 106     <span class="identifier">error_code</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">error</span><span class="special">,</span>
 107
 108     <span class="comment">// On success, the successfully connected endpoint.</span>
 109     <span class="comment">// Otherwise, a default-constructed endpoint.</span>
 110     <span class="keyword">typename</span> <span class="identifier">Protocol</span><span class="special">::</span><span class="identifier">endpoint</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">endpoint</span>
 111 <span class="special">);</span>
 112 </pre>
 113                     <p>
 114                       Regardless of whether the asynchronous operation completes
 115                       immediately or not, the handler will not be invoked from within
 116                       this function. Invocation of the handler will be performed
 117                       in a manner equivalent to using <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">post</span></code>.
 118                     </p>
 119                   </td>
 120 </tr>
 121 </tbody>
 122 </table></div>
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