libs/beast/doc/html/beast/ref/boost__beast__http__async_write_header.html

   1 <html>
   2 <head>
   3 <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
   4 <title>http::async_write_header</title>
   5 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
   6 <meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
   7 <link rel="home" href="../../index.html" title="Chapter&#160;1.&#160;Boost.Beast">
   8 <link rel="up" href="../ref.html" title="This Page Intentionally Left Blank 2/2">
   9 <link rel="prev" href="boost__beast__http__async_write/overload3.html" title="http::async_write (3 of 3 overloads)">
  10 <link rel="next" href="boost__beast__http__async_write_some.html" title="http::async_write_some">
  11 </head>
  12 <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
  13 <table cellpadding="2" width="100%"><tr>
  14 <td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../boost.png"></td>
  15 <td align="center"><a href="../../../../../../index.html">Home</a></td>
  16 <td align="center"><a href="../../../../../../libs/libraries.htm">Libraries</a></td>
  17 <td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
  18 <td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td>
  19 <td align="center"><a href="../../../../../../more/index.htm">More</a></td>
  20 </tr></table>
  21 <hr>
  22 <div class="spirit-nav">
  23 <a accesskey="p" href="boost__beast__http__async_write/overload3.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../ref.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="boost__beast__http__async_write_some.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a>
  24 </div>
  25 <div class="section">
  26 <div class="titlepage"><div><div><h4 class="title">
  27 <a name="beast.ref.boost__beast__http__async_write_header"></a><a class="link" href="boost__beast__http__async_write_header.html" title="http::async_write_header">http::async_write_header</a>
  28 </h4></div></div></div>
  29 <p>
  30         <a class="indexterm" name="idm45873506283920"></a>
  31 Write a header to a stream asynchronously using a
  32         serializer.
  33       </p>
  34 <h5>
  35 <a name="beast.ref.boost__beast__http__async_write_header.h0"></a>
  36         <span class="phrase"><a name="beast.ref.boost__beast__http__async_write_header.synopsis"></a></span><a class="link" href="boost__beast__http__async_write_header.html#beast.ref.boost__beast__http__async_write_header.synopsis">Synopsis</a>
  37       </h5>
  38 <p>
  39         Defined in header <code class="literal">&lt;<a href="../../../../../../boost/beast/http/write.hpp" target="_top">boost/beast/http/write.hpp</a>&gt;</code>
  40       </p>
  41 <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
  42     <span class="keyword">class</span> <a href="../../../../../../doc/html/boost_asio/reference/AsyncWriteStream.html" target="_top"><span class="emphasis"><em>AsyncWriteStream</em></span></a><span class="special">,</span>
  43     <span class="keyword">bool</span> <span class="identifier">isRequest</span><span class="special">,</span>
  44     <span class="keyword">class</span> <a class="link" href="../concepts/Body.html" title="Body"><span class="emphasis"><em>Body</em></span></a><span class="special">,</span>
  45     <span class="keyword">class</span> <a class="link" href="../concepts/Fields.html" title="Fields"><span class="emphasis"><em>Fields</em></span></a><span class="special">,</span>
  46     <span class="keyword">class</span> <a href="../../../../../../doc/html/boost_asio/reference/WriteHandler.html" target="_top"><span class="emphasis"><em>WriteHandler</em></span></a> <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">&lt;</span><span class="identifier">AsyncWriteStream</span><span class="special">&gt;&gt;&gt;</span>
  47 <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>
  48 <span class="identifier">async_write_header</span><span class="special">(</span>
  49     <span class="identifier">AsyncWriteStream</span><span class="special">&amp;</span> <span class="identifier">stream</span><span class="special">,</span>
  50     <span class="identifier">serializer</span><span class="special">&lt;</span> <span class="identifier">isRequest</span><span class="special">,</span> <span class="identifier">Body</span><span class="special">,</span> <span class="identifier">Fields</span> <span class="special">&gt;&amp;</span> <span class="identifier">sr</span><span class="special">,</span>
  51     <span class="identifier">WriteHandler</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">&lt;</span> <span class="identifier">AsyncWriteStream</span> <span class="special">&gt;&gt;{});</span>
  52 </pre>
  53 <h5>
  54 <a name="beast.ref.boost__beast__http__async_write_header.h1"></a>
  55         <span class="phrase"><a name="beast.ref.boost__beast__http__async_write_header.description"></a></span><a class="link" href="boost__beast__http__async_write_header.html#beast.ref.boost__beast__http__async_write_header.description">Description</a>
  56       </h5>
  57 <p>
  58         This function is used to write a header to a stream asynchronously using
  59         a caller-provided HTTP/1 serializer. The function call always returns immediately.
  60         The asynchronous operation will continue until one of the following conditions
  61         is true:
  62       </p>
  63 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
  64 <li class="listitem">
  65             The function <a class="link" href="boost__beast__http__serializer/is_header_done.html" title="http::serializer::is_header_done"><code class="computeroutput"><span class="identifier">http</span><span class="special">::</span><span class="identifier">serializer</span><span class="special">::</span><span class="identifier">is_header_done</span></code></a> returns <code class="computeroutput"><span class="keyword">true</span></code>
  66           </li>
  67 <li class="listitem">
  68             An error occurs.
  69           </li>
  70 </ul></div>
  71 <p>
  72         This operation is implemented in terms of zero or more calls to the stream's
  73         <code class="computeroutput"><span class="identifier">async_write_some</span></code> function,
  74         and is known as a <span class="emphasis"><em>composed operation</em></span>. The program must
  75         ensure that the stream performs no other writes until this operation completes.
  76       </p>
  77 <h5>
  78 <a name="beast.ref.boost__beast__http__async_write_header.h2"></a>
  79         <span class="phrase"><a name="beast.ref.boost__beast__http__async_write_header.parameters"></a></span><a class="link" href="boost__beast__http__async_write_header.html#beast.ref.boost__beast__http__async_write_header.parameters">Parameters</a>
  80       </h5>
  81 <div class="informaltable"><table class="table">
  82 <colgroup>
  83 <col>
  84 <col>
  85 </colgroup>
  86 <thead><tr>
  87 <th>
  88                 <p>
  89                   Name
  90                 </p>
  91               </th>
  92 <th>
  93                 <p>
  94                   Description
  95                 </p>
  96               </th>
  97 </tr></thead>
  98 <tbody>
  99 <tr>
 100 <td>
 101                 <p>
 102                   <code class="computeroutput"><span class="identifier">stream</span></code>
 103                 </p>
 104               </td>
 105 <td>
 106                 <p>
 107                   The stream to which the data is to be written. The type must support
 108                   the <span class="emphasis"><em>AsyncWriteStream</em></span> concept.
 109                 </p>
 110               </td>
 111 </tr>
 112 <tr>
 113 <td>
 114                 <p>
 115                   <code class="computeroutput"><span class="identifier">sr</span></code>
 116                 </p>
 117               </td>
 118 <td>
 119                 <p>
 120                   The serializer to use. The object must remain valid at least until
 121                   the handler is called; ownership is not transferred.
 122                 </p>
 123               </td>
 124 </tr>
 125 <tr>
 126 <td>
 127                 <p>
 128                   <code class="computeroutput"><span class="identifier">handler</span></code>
 129                 </p>
 130               </td>
 131 <td>
 132                 <p>
 133                   The completion handler to invoke when the operation completes.
 134                   The implementation takes ownership of the handler by performing
 135                   a decay-copy. The equivalent function signature of the handler
 136                   must be:
 137                 </p>
 138 <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>
 139     <span class="identifier">error_code</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">error</span><span class="special">,</span>        <span class="comment">// result of operation</span>
 140     <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">bytes_transferred</span>   <span class="comment">// the number of bytes written to the stream</span>
 141 <span class="special">);</span>
 142 </pre>
 143                 <p>
 144                   Regardless of whether the asynchronous operation completes immediately
 145                   or not, the handler will not be invoked from within this function.
 146                   Invocation of the handler will be performed in a manner equivalent
 147                   to using <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">post</span></code>.
 148                 </p>
 149               </td>
 150 </tr>
 151 </tbody>
 152 </table></div>
 153 <h5>
 154 <a name="beast.ref.boost__beast__http__async_write_header.h3"></a>
 155         <span class="phrase"><a name="beast.ref.boost__beast__http__async_write_header.remarks"></a></span><a class="link" href="boost__beast__http__async_write_header.html#beast.ref.boost__beast__http__async_write_header.remarks">Remarks</a>
 156       </h5>
 157 <p>
 158         The implementation will call <a class="link" href="boost__beast__http__serializer/split.html" title="http::serializer::split"><code class="computeroutput"><span class="identifier">http</span><span class="special">::</span><span class="identifier">serializer</span><span class="special">::</span><span class="identifier">split</span></code></a> with the value <code class="computeroutput"><span class="keyword">true</span></code> on the serializer passed in.
 159       </p>
 160 <h5>
 161 <a name="beast.ref.boost__beast__http__async_write_header.h4"></a>
 162         <span class="phrase"><a name="beast.ref.boost__beast__http__async_write_header.see_also"></a></span><a class="link" href="boost__beast__http__async_write_header.html#beast.ref.boost__beast__http__async_write_header.see_also">See Also</a>
 163       </h5>
 164 <p>
 165         <a class="link" href="boost__beast__http__serializer.html" title="http::serializer"><code class="computeroutput"><span class="identifier">http</span><span class="special">::</span><span class="identifier">serializer</span></code></a>
 166       </p>
 167 <p>
 168         Convenience header <code class="literal">&lt;<a href="../../../../../../boost/beast/http.hpp" target="_top">boost/beast/http.hpp</a>&gt;</code>
 169       </p>
 170 </div>
 171 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 172 <td align="left"></td>
 173 <td align="right"><div class="copyright-footer">Copyright &#169; 2016-2019 Vinnie
 174       Falco<p>
 175         Distributed under the Boost Software License, Version 1.0. (See accompanying
 176         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>)
 177       </p>
 178 </div></td>
 179 </tr></table>
 180 <hr>
 181 <div class="spirit-nav">
 182 <a accesskey="p" href="boost__beast__http__async_write/overload3.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../ref.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="boost__beast__http__async_write_some.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a>
 183 </div>
 184 </body>
 185 </html>