1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>http::parser::on_chunk_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 1. 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The invocation happens after the chunk 52 header is available but before any body octets have been parsed. The extensions 53 are provided in raw, validated form, use <a class="link" href="../boost__beast__http__basic_chunk_extensions/parse.html" title="http::basic_chunk_extensions::parse"><code class="computeroutput"><span class="identifier">chunk_extensions</span><span class="special">::</span><span class="identifier">parse</span></code></a> to parse the extensions 54 into a structured container for easier access. The implementation type-erases 55 the callback without requiring a dynamic allocation. For this reason, the 56 callback object is passed by a non-constant reference. 57 </p> 58<h6> 59<a name="beast.ref.boost__beast__http__parser.on_chunk_header.h2"></a> 60 <span class="phrase"><a name="beast.ref.boost__beast__http__parser.on_chunk_header.example"></a></span><a class="link" href="on_chunk_header.html#beast.ref.boost__beast__http__parser.on_chunk_header.example">Example</a> 61 </h6> 62<pre class="programlisting"><span class="keyword">auto</span> <span class="identifier">callback</span> <span class="special">=</span> 63 <span class="special">[](</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">uint64_t</span> <span class="identifier">size</span><span class="special">,</span> <span class="identifier">string_view</span> <span class="identifier">extensions</span><span class="special">,</span> <span class="identifier">error_code</span><span class="special">&</span> <span class="identifier">ec</span><span class="special">)</span> 64 <span class="special">{</span> 65 <span class="comment">//...</span> 66 <span class="special">};</span> 67<span class="identifier">parser</span><span class="special">.</span><span class="identifier">on_chunk_header</span><span class="special">(</span><span class="identifier">callback</span><span class="special">);</span> 68</pre> 69<h6> 70<a name="beast.ref.boost__beast__http__parser.on_chunk_header.h3"></a> 71 <span class="phrase"><a name="beast.ref.boost__beast__http__parser.on_chunk_header.parameters"></a></span><a class="link" href="on_chunk_header.html#beast.ref.boost__beast__http__parser.on_chunk_header.parameters">Parameters</a> 72 </h6> 73<div class="informaltable"><table class="table"> 74<colgroup> 75<col> 76<col> 77</colgroup> 78<thead><tr> 79<th> 80 <p> 81 Name 82 </p> 83 </th> 84<th> 85 <p> 86 Description 87 </p> 88 </th> 89</tr></thead> 90<tbody><tr> 91<td> 92 <p> 93 <code class="computeroutput"><span class="identifier">cb</span></code> 94 </p> 95 </td> 96<td> 97 <p> 98 The function to set, which must be invocable with this equivalent 99 signature: 100 </p> 101<pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="keyword">void</span> 102<span class="identifier">on_chunk_header</span><span class="special">(</span> 103 <span class="identifier">std</span><span class="special">::</span><span class="identifier">uint64_t</span> <span class="identifier">size</span><span class="special">,</span> <span class="comment">// Size of the chunk, zero for the last chunk</span> 104 <span class="identifier">string_view</span> <span class="identifier">extensions</span><span class="special">,</span> <span class="comment">// The chunk-extensions in raw form</span> 105 <span class="identifier">error_code</span><span class="special">&</span> <span class="identifier">ec</span><span class="special">);</span> <span class="comment">// May be set by the callback to indicate an error</span> 106</pre> 107 </td> 108</tr></tbody> 109</table></div> 110</div> 111<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 112<td align="left"></td> 113<td align="right"><div class="copyright-footer">Copyright © 2016-2019 Vinnie 114 Falco<p> 115 Distributed under the Boost Software License, Version 1.0. (See accompanying 116 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>) 117 </p> 118</div></td> 119</tr></table> 120<hr> 121<div class="spirit-nav"> 122<a accesskey="p" href="release.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../boost__beast__http__parser.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="on_chunk_body.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 123</div> 124</body> 125</html> 126
