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  26 <div class="titlepage"><div><div><h6 class="title">
  27 <a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1"></a><a class="link" href="overload1.html" title="websocket::stream::async_accept (1 of 3 overloads)">websocket::stream::async_accept
  28           (1 of 3 overloads)</a>
  29 </h6></div></div></div>
  30 <p>
  31             Perform the WebSocket handshake asynchronously in the server role.
  32           </p>
  33 <h7><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.h0"></a>
  34             <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.synopsis"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.async_accept.overload1.synopsis">Synopsis</a>
  35           </h7><pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
  36     <span class="keyword">class</span> <span class="identifier">AcceptHandler</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;&gt;</span>
  37 <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>
  38 <span class="identifier">async_accept</span><span class="special">(</span>
  39     <span class="identifier">AcceptHandler</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>
  40 </pre>
  41 <h7><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.h1"></a>
  42             <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.description"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.async_accept.overload1.description">Description</a>
  43           </h7><p>
  44             This initiating function is used to asynchronously begin performing the
  45             <a href="https://en.wikipedia.org/wiki/WebSocket#Protocol_handshake" target="_top">WebSocket
  46             handshake</a>, required before messages can be sent and received.
  47             During the handshake, the client sends the Websocket Upgrade HTTP request,
  48             and the server replies with an HTTP response indicating the result of
  49             the handshake. This call always returns immediately. The asynchronous
  50             operation will continue until one of the following conditions is true:
  51           </p>
  52 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
  53 <li class="listitem">
  54                 The request is received and the response is sent.
  55               </li>
  56 <li class="listitem">
  57                 An error occurs.
  58               </li>
  59 </ul></div>
  60 <p>
  61             The algorithm, known as a <span class="emphasis"><em>composed asynchronous operation</em></span>,
  62             is implemented in terms of calls to the next layer's <code class="computeroutput"><span class="identifier">async_read_some</span></code>
  63             and <code class="computeroutput"><span class="identifier">async_write_some</span></code>
  64             functions. No other operation may be performed on the stream until this
  65             operation completes. If a valid upgrade request is received, an HTTP
  66             response with a <a href="https://tools.ietf.org/html/rfc7230#section-3.1.2" target="_top">status-code</a>
  67             of <a class="link" href="../../boost__beast__http__status.html" title="http::status"><code class="computeroutput"><span class="identifier">http</span><span class="special">::</span><span class="identifier">switching_protocols</span></code></a> is sent
  68             to the peer, otherwise a non-successful error is associated with the
  69             operation. If the request size exceeds the capacity of the stream's internal
  70             buffer, the error <a class="link" href="../../boost__beast__websocket__error.html" title="websocket::error"><code class="computeroutput"><span class="identifier">websocket</span><span class="special">::</span><span class="identifier">buffer_overflow</span></code></a> will be indicated.
  71             To handle larger requests, an application should read the HTTP request
  72             directly using <a class="link" href="../../boost__beast__http__async_read.html" title="http::async_read"><code class="computeroutput"><span class="identifier">http</span><span class="special">::</span><span class="identifier">async_read</span></code></a> and then pass the
  73             request to the appropriate overload of <a class="link" href="../accept.html" title="websocket::stream::accept"><code class="computeroutput"><span class="identifier">websocket</span><span class="special">::</span><span class="identifier">stream</span><span class="special">::</span><span class="identifier">accept</span></code></a> or <a class="link" href="../async_accept.html" title="websocket::stream::async_accept"><code class="computeroutput"><span class="identifier">websocket</span><span class="special">::</span><span class="identifier">stream</span><span class="special">::</span><span class="identifier">async_accept</span></code></a>
  74           </p>
  75 <h7><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.h2"></a>
  76             <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.parameters"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.async_accept.overload1.parameters">Parameters</a>
  77           </h7><div class="informaltable"><table class="table">
  78 <colgroup>
  79 <col>
  80 <col>
  81 </colgroup>
  82 <thead><tr>
  83 <th>
  84                     <p>
  85                       Name
  86                     </p>
  87                   </th>
  88 <th>
  89                     <p>
  90                       Description
  91                     </p>
  92                   </th>
  93 </tr></thead>
  94 <tbody><tr>
  95 <td>
  96                     <p>
  97                       <code class="computeroutput"><span class="identifier">handler</span></code>
  98                     </p>
  99                   </td>
 100 <td>
 101                     <p>
 102                       The completion handler to invoke when the operation completes.
 103                       The implementation takes ownership of the handler by performing
 104                       a decay-copy. The equivalent function signature of the handler
 105                       must be:
 106                     </p>
 107 <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>
 108     <span class="identifier">error_code</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">ec</span>    <span class="comment">// Result of operation</span>
 109 <span class="special">);</span>
 110 </pre>
 111                     <p>
 112                       Regardless of whether the asynchronous operation completes
 113                       immediately or not, the handler will not be invoked from within
 114                       this function. Invocation of the handler will be performed
 115                       in a manner equivalent to using <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">post</span></code>.
 116                     </p>
 117                   </td>
 118 </tr></tbody>
 119 </table></div>
 120 <h7><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.h3"></a>
 121             <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.see_also"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.async_accept.overload1.see_also">See
 122             Also</a>
 123           </h7><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
 124                 <a href="https://tools.ietf.org/html/rfc6455#section-4.2" target="_top">Websocket
 125                 Opening Handshake Server Requirements (RFC6455)</a>
 126               </li></ul></div>
 127 </div>
 128 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 129 <td align="left"></td>
 130 <td align="right"><div class="copyright-footer">Copyright &#169; 2016-2019 Vinnie
 131       Falco<p>
 132         Distributed under the Boost Software License, Version 1.0. (See accompanying
 133         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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