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  26 <div class="titlepage"><div><div><h4 class="title">
  27 <a name="boost_asio.reference.connect.overload4"></a><a class="link" href="overload4.html" title="connect (4 of 8 overloads)">connect (4
  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">Iterator</span> <span class="identifier">end</span><span class="special">,</span>
  41     <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>
  42 </pre>
  43 <p>
  44           This function attempts to connect a socket to one of a sequence of endpoints.
  45           It does this by repeated calls to the socket's <code class="computeroutput"><span class="identifier">connect</span></code>
  46           member function, once for each endpoint in the sequence, until a connection
  47           is successfully established.
  48         </p>
  49 <h6>
  50 <a name="boost_asio.reference.connect.overload4.h0"></a>
  51           <span class="phrase"><a name="boost_asio.reference.connect.overload4.parameters"></a></span><a class="link" href="overload4.html#boost_asio.reference.connect.overload4.parameters">Parameters</a>
  52         </h6>
  53 <div class="variablelist">
  54 <p class="title"><b></b></p>
  55 <dl class="variablelist">
  56 <dt><span class="term">s</span></dt>
  57 <dd><p>
  58                 The socket to be connected. If the socket is already open, it will
  59                 be closed.
  60               </p></dd>
  61 <dt><span class="term">begin</span></dt>
  62 <dd><p>
  63                 An iterator pointing to the start of a sequence of endpoints.
  64               </p></dd>
  65 <dt><span class="term">end</span></dt>
  66 <dd><p>
  67                 An iterator pointing to the end of a sequence of endpoints.
  68               </p></dd>
  69 <dt><span class="term">ec</span></dt>
  70 <dd><p>
  71                 Set to indicate what error occurred, if any. If the sequence is empty,
  72                 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
  73                 the error from the last connection attempt.
  74               </p></dd>
  75 </dl>
  76 </div>
  77 <h6>
  78 <a name="boost_asio.reference.connect.overload4.h1"></a>
  79           <span class="phrase"><a name="boost_asio.reference.connect.overload4.return_value"></a></span><a class="link" href="overload4.html#boost_asio.reference.connect.overload4.return_value">Return Value</a>
  80         </h6>
  81 <p>
  82           On success, an iterator denoting the successfully connected endpoint. Otherwise,
  83           the end iterator.
  84         </p>
  85 <h6>
  86 <a name="boost_asio.reference.connect.overload4.h2"></a>
  87           <span class="phrase"><a name="boost_asio.reference.connect.overload4.example"></a></span><a class="link" href="overload4.html#boost_asio.reference.connect.overload4.example">Example</a>
  88         </h6>
  89 <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>
  90 <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>
  91 <span class="identifier">tcp</span><span class="special">::</span><span class="identifier">resolver</span><span class="special">::</span><span class="identifier">iterator</span> <span class="identifier">i</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">end</span><span class="special">;</span>
  92 <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>
  93 <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>
  94 <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">i</span><span class="special">,</span> <span class="identifier">end</span><span class="special">,</span> <span class="identifier">ec</span><span class="special">);</span>
  95 <span class="keyword">if</span> <span class="special">(</span><span class="identifier">ec</span><span class="special">)</span>
  96 <span class="special">{</span>
  97   <span class="comment">// An error occurred.</span>
  98 <span class="special">}</span>
  99 </pre>
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