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  27 <a name="boost_asio.reference.basic_datagram_socket.async_receive_from.overload1"></a><a class="link" href="overload1.html" title="basic_datagram_socket::async_receive_from (1 of 2 overloads)">basic_datagram_socket::async_receive_from
  28           (1 of 2 overloads)</a>
  29 </h5></div></div></div>
  30 <p>
  31             Start an asynchronous receive.
  32           </p>
  33 <pre class="programlisting">template&lt;
  34     typename <a class="link" href="../../MutableBufferSequence.html" title="Mutable buffer sequence requirements">MutableBufferSequence</a>,
  35     typename <a class="link" href="../../ReadHandler.html" title="Read handler requirements">ReadHandler</a> = <a class="link" href="../../asynchronous_operations.html#boost_asio.reference.asynchronous_operations.default_completion_tokens"><span class="emphasis"><em>DEFAULT</em></span></a>&gt;
  36 <a class="link" href="../../asynchronous_operations.html#boost_asio.reference.asynchronous_operations.automatic_deduction_of_initiating_function_return_type"><span class="emphasis"><em>DEDUCED</em></span></a> async_receive_from(
  37     const MutableBufferSequence &amp; buffers,
  38     endpoint_type &amp; sender_endpoint,
  39     ReadHandler &amp;&amp; handler = <a class="link" href="../../asynchronous_operations.html#boost_asio.reference.asynchronous_operations.default_completion_tokens"><span class="emphasis"><em>DEFAULT</em></span></a>);
  40 </pre>
  41 <p>
  42             This function is used to asynchronously receive a datagram. The function
  43             call always returns immediately.
  44           </p>
  45 <h6>
  46 <a name="boost_asio.reference.basic_datagram_socket.async_receive_from.overload1.h0"></a>
  47             <span class="phrase"><a name="boost_asio.reference.basic_datagram_socket.async_receive_from.overload1.parameters"></a></span><a class="link" href="overload1.html#boost_asio.reference.basic_datagram_socket.async_receive_from.overload1.parameters">Parameters</a>
  48           </h6>
  49 <div class="variablelist">
  50 <p class="title"><b></b></p>
  51 <dl class="variablelist">
  52 <dt><span class="term">buffers</span></dt>
  53 <dd><p>
  54                   One or more buffers into which the data will be received. Although
  55                   the buffers object may be copied as necessary, ownership of the
  56                   underlying memory blocks is retained by the caller, which must
  57                   guarantee that they remain valid until the handler is called.
  58                 </p></dd>
  59 <dt><span class="term">sender_endpoint</span></dt>
  60 <dd><p>
  61                   An endpoint object that receives the endpoint of the remote sender
  62                   of the datagram. Ownership of the sender_endpoint object is retained
  63                   by the caller, which must guarantee that it is valid until the
  64                   handler is called.
  65                 </p></dd>
  66 <dt><span class="term">handler</span></dt>
  67 <dd>
  68 <p>
  69                   The handler to be called when the receive operation completes.
  70                   Copies will be made of the handler as required. The function signature
  71                   of the handler must be:
  72 </p>
  73 <pre class="programlisting">void handler(
  74   const boost::system::error_code&amp; error, // Result of operation.
  75   std::size_t bytes_transferred           // Number of bytes received.
  76 );
  77 </pre>
  78 <p>
  79                   Regardless of whether the asynchronous operation completes immediately
  80                   or not, the handler will not be invoked from within this function.
  81                   On immediate completion, invocation of the handler will be performed
  82                   in a manner equivalent to using <a class="link" href="../../post.html" title="post"><code class="computeroutput">post</code></a>.
  83                 </p>
  84 </dd>
  85 </dl>
  86 </div>
  87 <h6>
  88 <a name="boost_asio.reference.basic_datagram_socket.async_receive_from.overload1.h1"></a>
  89             <span class="phrase"><a name="boost_asio.reference.basic_datagram_socket.async_receive_from.overload1.example"></a></span><a class="link" href="overload1.html#boost_asio.reference.basic_datagram_socket.async_receive_from.overload1.example">Example</a>
  90           </h6>
  91 <p>
  92             To receive into a single data buffer use the <a class="link" href="../../buffer.html" title="buffer"><code class="computeroutput">buffer</code></a>
  93             function as follows:
  94           </p>
  95 <pre class="programlisting">socket.async_receive_from(
  96     boost::asio::buffer(data, size), sender_endpoint, handler);
  97 </pre>
  98 <p>
  99             See the <a class="link" href="../../buffer.html" title="buffer"><code class="computeroutput">buffer</code></a>
 100             documentation for information on receiving into multiple buffers in one
 101             go, and how to use it with arrays, boost::array or std::vector.
 102           </p>
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