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diff --git a/doc/html/boost_asio/reference/async_read_until/overload2.html b/doc/html/boost_asio/reference/async_read_until/overload2.html new file mode 100755 index 0000000000..d559500688 --- /dev/null +++ b/doc/html/boost_asio/reference/async_read_until/overload2.html @@ -0,0 +1,186 @@ +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>async_read_until (2 of 4 overloads)</title> +<link rel="stylesheet" href="../../../../../doc/src/boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.76.1"> +<link rel="home" href="../../../boost_asio.html" title="Boost.Asio"> +<link rel="up" href="../async_read_until.html" title="async_read_until"> +<link rel="prev" href="overload1.html" title="async_read_until (1 of 4 overloads)"> +<link rel="next" href="overload3.html" title="async_read_until (3 of 4 overloads)"> +</head> +<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> +<table cellpadding="2" width="100%"><tr> +<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../boost.png"></td> +<td align="center"><a href="../../../../../index.html">Home</a></td> +<td align="center"><a href="../../../../../libs/libraries.htm">Libraries</a></td> +<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> +<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> +<td align="center"><a href="../../../../../more/index.htm">More</a></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="overload1.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../async_read_until.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../boost_asio.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="overload3.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a> +</div> +<div class="section"> +<div class="titlepage"><div><div><h4 class="title"> +<a name="boost_asio.reference.async_read_until.overload2"></a><a class="link" href="overload2.html" title="async_read_until (2 of 4 overloads)">async_read_until + (2 of 4 overloads)</a> +</h4></div></div></div> +<p> + Start an asynchronous operation to read data into a streambuf until it + contains a specified delimiter. + </p> +<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> + <span class="keyword">typename</span> <a class="link" href="../AsyncReadStream.html" title="Buffer-oriented asynchronous read stream requirements">AsyncReadStream</a><span class="special">,</span> + <span class="keyword">typename</span> <span class="identifier">Allocator</span><span class="special">,</span> + <span class="keyword">typename</span> <a class="link" href="../ReadHandler.html" title="Read handler requirements">ReadHandler</a><span class="special">></span> +<span class="keyword">void</span> <span class="identifier">async_read_until</span><span class="special">(</span> + <span class="identifier">AsyncReadStream</span> <span class="special">&</span> <span class="identifier">s</span><span class="special">,</span> + <span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">basic_streambuf</span><span class="special"><</span> <span class="identifier">Allocator</span> <span class="special">></span> <span class="special">&</span> <span class="identifier">b</span><span class="special">,</span> + <span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="special">&</span> <span class="identifier">delim</span><span class="special">,</span> + <span class="identifier">ReadHandler</span> <span class="identifier">handler</span><span class="special">);</span> +</pre> +<p> + This function is used to asynchronously read data into the specified streambuf + until the streambuf's get area contains the specified delimiter. The function + call always returns immediately. The asynchronous operation will continue + until one of the following conditions is true: + </p> +<div class="itemizedlist"><ul class="itemizedlist" type="disc"> +<li class="listitem"> + The get area of the streambuf contains the specified delimiter. + </li> +<li class="listitem"> + An error occurred. + </li> +</ul></div> +<p> + This operation is implemented in terms of zero or more calls to the stream's + async_read_some function, and is known as a <span class="bold"><strong>composed + operation</strong></span>. If the streambuf's get area already contains the + delimiter, this asynchronous operation completes immediately. The program + must ensure that the stream performs no other read operations (such as + async_read, async_read_until, the stream's async_read_some function, or + any other composed operations that perform reads) until this operation + completes. + </p> +<h6> +<a name="boost_asio.reference.async_read_until.overload2.h0"></a> + <span><a name="boost_asio.reference.async_read_until.overload2.parameters"></a></span><a class="link" href="overload2.html#boost_asio.reference.async_read_until.overload2.parameters">Parameters</a> + </h6> +<div class="variablelist"> +<p class="title"><b></b></p> +<dl> +<dt><span class="term">s</span></dt> +<dd><p> + The stream from which the data is to be read. The type must support + the AsyncReadStream concept. + </p></dd> +<dt><span class="term">b</span></dt> +<dd><p> + A streambuf object into which the data will be read. Ownership of + the streambuf is retained by the caller, which must guarantee that + it remains valid until the handler is called. + </p></dd> +<dt><span class="term">delim</span></dt> +<dd><p> + The delimiter string. + </p></dd> +<dt><span class="term">handler</span></dt> +<dd> +<p> + The handler to be called when the read operation completes. Copies + will be made of the handler as required. The function signature of + the handler must be: +</p> +<pre class="programlisting"><span class="keyword">void</span> <span class="identifier">handler</span><span class="special">(</span> + <span class="comment">// Result of operation.</span> + <span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">system</span><span class="special">::</span><span class="identifier">error_code</span><span class="special">&</span> <span class="identifier">error</span><span class="special">,</span> + + <span class="comment">// The number of bytes in the streambuf's get</span> + <span class="comment">// area up to and including the delimiter.</span> + <span class="comment">// 0 if an error occurred.</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">bytes_transferred</span> +<span class="special">);</span> +</pre> +<p> + Regardless of whether the asynchronous operation completes immediately + or not, the handler will not be invoked from within this function. + Invocation of the handler will be performed in a manner equivalent + to using <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">io_service</span><span class="special">::</span><span class="identifier">post</span><span class="special">()</span></code>. + </p> +</dd> +</dl> +</div> +<h6> +<a name="boost_asio.reference.async_read_until.overload2.h1"></a> + <span><a name="boost_asio.reference.async_read_until.overload2.remarks"></a></span><a class="link" href="overload2.html#boost_asio.reference.async_read_until.overload2.remarks">Remarks</a> + </h6> +<p> + After a successful async_read_until operation, the streambuf may contain + additional data beyond the delimiter. An application will typically leave + that data in the streambuf for a subsequent async_read_until operation + to examine. + </p> +<h6> +<a name="boost_asio.reference.async_read_until.overload2.h2"></a> + <span><a name="boost_asio.reference.async_read_until.overload2.example"></a></span><a class="link" href="overload2.html#boost_asio.reference.async_read_until.overload2.example">Example</a> + </h6> +<p> + To asynchronously read data into a streambuf until a newline is encountered: + </p> +<pre class="programlisting"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">streambuf</span> <span class="identifier">b</span><span class="special">;</span> +<span class="special">...</span> +<span class="keyword">void</span> <span class="identifier">handler</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">system</span><span class="special">::</span><span class="identifier">error_code</span><span class="special">&</span> <span class="identifier">e</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">size</span><span class="special">)</span> +<span class="special">{</span> + <span class="keyword">if</span> <span class="special">(!</span><span class="identifier">e</span><span class="special">)</span> + <span class="special">{</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">istream</span> <span class="identifier">is</span><span class="special">(&</span><span class="identifier">b</span><span class="special">);</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">line</span><span class="special">;</span> + <span class="identifier">std</span><span class="special">::</span><span class="identifier">getline</span><span class="special">(</span><span class="identifier">is</span><span class="special">,</span> <span class="identifier">line</span><span class="special">);</span> + <span class="special">...</span> + <span class="special">}</span> +<span class="special">}</span> +<span class="special">...</span> +<span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">async_read_until</span><span class="special">(</span><span class="identifier">s</span><span class="special">,</span> <span class="identifier">b</span><span class="special">,</span> <span class="string">"\r\n"</span><span class="special">,</span> <span class="identifier">handler</span><span class="special">);</span> +</pre> +<p> + After the <code class="computeroutput"><span class="identifier">async_read_until</span></code> + operation completes successfully, the buffer <code class="computeroutput"><span class="identifier">b</span></code> + contains the delimiter: + </p> +<pre class="programlisting"><span class="special">{</span> <span class="char">'a'</span><span class="special">,</span> <span class="char">'b'</span><span class="special">,</span> <span class="special">...,</span> <span class="char">'c'</span><span class="special">,</span> <span class="char">'\r'</span><span class="special">,</span> <span class="char">'\n'</span><span class="special">,</span> <span class="char">'d'</span><span class="special">,</span> <span class="char">'e'</span><span class="special">,</span> <span class="special">...</span> <span class="special">}</span> +</pre> +<p> + The call to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">getline</span></code> then extracts the data up to + and including the delimiter, so that the string <code class="computeroutput"><span class="identifier">line</span></code> + contains: + </p> +<pre class="programlisting"><span class="special">{</span> <span class="char">'a'</span><span class="special">,</span> <span class="char">'b'</span><span class="special">,</span> <span class="special">...,</span> <span class="char">'c'</span><span class="special">,</span> <span class="char">'\r'</span><span class="special">,</span> <span class="char">'\n'</span> <span class="special">}</span> +</pre> +<p> + The remaining data is left in the buffer <code class="computeroutput"><span class="identifier">b</span></code> + as follows: + </p> +<pre class="programlisting"><span class="special">{</span> <span class="char">'d'</span><span class="special">,</span> <span class="char">'e'</span><span class="special">,</span> <span class="special">...</span> <span class="special">}</span> +</pre> +<p> + This data may be the start of a new line, to be extracted by a subsequent + <code class="computeroutput"><span class="identifier">async_read_until</span></code> operation. + </p> +</div> +<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> +<td align="left"></td> +<td align="right"><div class="copyright-footer">Copyright © 2003-2012 Christopher M. Kohlhoff<p> + Distributed under the Boost Software License, Version 1.0. (See accompanying + 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>) + </p> +</div></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="overload1.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../async_read_until.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../boost_asio.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="overload3.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a> +</div> +</body> +</html> |