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  26 <div class="titlepage"><div><div><h3 class="title">
  27 <a name="boost_asio.reference.ip__unicast__hops"></a><a class="link" href="ip__unicast__hops.html" title="ip::unicast::hops">ip::unicast::hops</a>
  28 </h3></div></div></div>
  29 <p>
  30         <a class="indexterm" name="idp153603840"></a>
  31 Socket option for time-to-live associated with outgoing
  32         unicast packets.
  33       </p>
  34 <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">implementation_defined</span> <span class="identifier">hops</span><span class="special">;</span>
  35 </pre>
  36 <p>
  37         Implements the IPPROTO_IP/IP_UNICAST_TTL socket option.
  38       </p>
  39 <h5>
  40 <a name="boost_asio.reference.ip__unicast__hops.h0"></a>
  41         <span class="phrase"><a name="boost_asio.reference.ip__unicast__hops.examples"></a></span><a class="link" href="ip__unicast__hops.html#boost_asio.reference.ip__unicast__hops.examples">Examples</a>
  42       </h5>
  43 <p>
  44         Setting the option:
  45       </p>
  46 <pre class="programlisting"><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">udp</span><span class="special">::</span><span class="identifier">socket</span> <span class="identifier">socket</span><span class="special">(</span><span class="identifier">io_service</span><span class="special">);</span>
  47 <span class="special">...</span>
  48 <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">unicast</span><span class="special">::</span><span class="identifier">hops</span> <span class="identifier">option</span><span class="special">(</span><span class="number">4</span><span class="special">);</span>
  49 <span class="identifier">socket</span><span class="special">.</span><span class="identifier">set_option</span><span class="special">(</span><span class="identifier">option</span><span class="special">);</span>
  50 </pre>
  51 <p>
  52         Getting the current option value:
  53       </p>
  54 <pre class="programlisting"><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">udp</span><span class="special">::</span><span class="identifier">socket</span> <span class="identifier">socket</span><span class="special">(</span><span class="identifier">io_service</span><span class="special">);</span>
  55 <span class="special">...</span>
  56 <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">unicast</span><span class="special">::</span><span class="identifier">hops</span> <span class="identifier">option</span><span class="special">;</span>
  57 <span class="identifier">socket</span><span class="special">.</span><span class="identifier">get_option</span><span class="special">(</span><span class="identifier">option</span><span class="special">);</span>
  58 <span class="keyword">int</span> <span class="identifier">ttl</span> <span class="special">=</span> <span class="identifier">option</span><span class="special">.</span><span class="identifier">value</span><span class="special">();</span>
  59 </pre>
  60 <h5>
  61 <a name="boost_asio.reference.ip__unicast__hops.h1"></a>
  62         <span class="phrase"><a name="boost_asio.reference.ip__unicast__hops.requirements"></a></span><a class="link" href="ip__unicast__hops.html#boost_asio.reference.ip__unicast__hops.requirements">Requirements</a>
  63       </h5>
  64 <p>
  65         <span class="emphasis"><em>Header: </em></span><code class="literal">boost/asio/ip/unicast.hpp</code>
  66       </p>
  67 <p>
  68         <span class="emphasis"><em>Convenience header: </em></span><code class="literal">boost/asio.hpp</code>
  69       </p>
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