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  26 <div class="titlepage"><div><div><h4 class="title">
  27 <a name="boost_asio.reference.connect.overload2"></a><a class="link" href="overload2.html" title="connect (2 of 8 overloads)">connect (2
  28         of 8 overloads)</a>
  29 </h4></div></div></div>
  30 <p>
  31           Establishes a socket connection by trying each endpoint in a sequence.
  32         </p>
  33 <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
  34     <span class="keyword">typename</span> <a class="link" href="../Protocol.html" title="Protocol requirements">Protocol</a><span class="special">,</span>
  35     <span class="keyword">typename</span> <a class="link" href="../SocketService.html" title="Socket service requirements">SocketService</a><span class="special">,</span>
  36     <span class="keyword">typename</span> <span class="identifier">Iterator</span><span class="special">&gt;</span>
  37 <span class="identifier">Iterator</span> <span class="identifier">connect</span><span class="special">(</span>
  38     <span class="identifier">basic_socket</span><span class="special">&lt;</span> <span class="identifier">Protocol</span><span class="special">,</span> <span class="identifier">SocketService</span> <span class="special">&gt;</span> <span class="special">&amp;</span> <span class="identifier">s</span><span class="special">,</span>
  39     <span class="identifier">Iterator</span> <span class="identifier">begin</span><span class="special">,</span>
  40     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">system</span><span class="special">::</span><span class="identifier">error_code</span> <span class="special">&amp;</span> <span class="identifier">ec</span><span class="special">);</span>
  41 </pre>
  42 <p>
  43           This function attempts to connect a socket to one of a sequence of endpoints.
  44           It does this by repeated calls to the socket's <code class="computeroutput"><span class="identifier">connect</span></code>
  45           member function, once for each endpoint in the sequence, until a connection
  46           is successfully established.
  47         </p>
  48 <h6>
  49 <a name="boost_asio.reference.connect.overload2.h0"></a>
  50           <span class="phrase"><a name="boost_asio.reference.connect.overload2.parameters"></a></span><a class="link" href="overload2.html#boost_asio.reference.connect.overload2.parameters">Parameters</a>
  51         </h6>
  52 <div class="variablelist">
  53 <p class="title"><b></b></p>
  54 <dl class="variablelist">
  55 <dt><span class="term">s</span></dt>
  56 <dd><p>
  57                 The socket to be connected. If the socket is already open, it will
  58                 be closed.
  59               </p></dd>
  60 <dt><span class="term">begin</span></dt>
  61 <dd><p>
  62                 An iterator pointing to the start of a sequence of endpoints.
  63               </p></dd>
  64 <dt><span class="term">ec</span></dt>
  65 <dd><p>
  66                 Set to indicate what error occurred, if any. If the sequence is empty,
  67                 set to <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">error</span><span class="special">::</span><span class="identifier">not_found</span></code>. Otherwise, contains
  68                 the error from the last connection attempt.
  69               </p></dd>
  70 </dl>
  71 </div>
  72 <h6>
  73 <a name="boost_asio.reference.connect.overload2.h1"></a>
  74           <span class="phrase"><a name="boost_asio.reference.connect.overload2.return_value"></a></span><a class="link" href="overload2.html#boost_asio.reference.connect.overload2.return_value">Return Value</a>
  75         </h6>
  76 <p>
  77           On success, an iterator denoting the successfully connected endpoint. Otherwise,
  78           the end iterator.
  79         </p>
  80 <h6>
  81 <a name="boost_asio.reference.connect.overload2.h2"></a>
  82           <span class="phrase"><a name="boost_asio.reference.connect.overload2.remarks"></a></span><a class="link" href="overload2.html#boost_asio.reference.connect.overload2.remarks">Remarks</a>
  83         </h6>
  84 <p>
  85           This overload assumes that a default constructed object of type <code class="computeroutput"><span class="identifier">Iterator</span></code> represents the end of the sequence.
  86           This is a valid assumption for iterator types such as <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">ip</span><span class="special">::</span><span class="identifier">tcp</span><span class="special">::</span><span class="identifier">resolver</span><span class="special">::</span><span class="identifier">iterator</span></code>.
  87         </p>
  88 <h6>
  89 <a name="boost_asio.reference.connect.overload2.h3"></a>
  90           <span class="phrase"><a name="boost_asio.reference.connect.overload2.example"></a></span><a class="link" href="overload2.html#boost_asio.reference.connect.overload2.example">Example</a>
  91         </h6>
  92 <pre class="programlisting"><span class="identifier">tcp</span><span class="special">::</span><span class="identifier">resolver</span> <span class="identifier">r</span><span class="special">(</span><span class="identifier">io_service</span><span class="special">);</span>
  93 <span class="identifier">tcp</span><span class="special">::</span><span class="identifier">resolver</span><span class="special">::</span><span class="identifier">query</span> <span class="identifier">q</span><span class="special">(</span><span class="string">"host"</span><span class="special">,</span> <span class="string">"service"</span><span class="special">);</span>
  94 <span class="identifier">tcp</span><span class="special">::</span><span class="identifier">socket</span> <span class="identifier">s</span><span class="special">(</span><span class="identifier">io_service</span><span class="special">);</span>
  95 <span class="identifier">boost</span><span class="special">::</span><span class="identifier">system</span><span class="special">::</span><span class="identifier">error_code</span> <span class="identifier">ec</span><span class="special">;</span>
  96 <span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">connect</span><span class="special">(</span><span class="identifier">s</span><span class="special">,</span> <span class="identifier">r</span><span class="special">.</span><span class="identifier">resolve</span><span class="special">(</span><span class="identifier">q</span><span class="special">),</span> <span class="identifier">ec</span><span class="special">);</span>
  97 <span class="keyword">if</span> <span class="special">(</span><span class="identifier">ec</span><span class="special">)</span>
  98 <span class="special">{</span>
  99   <span class="comment">// An error occurred.</span>
 100 <span class="special">}</span>
 101 </pre>
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