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diff --git a/doc/html/boost_asio/tutorial/tuttimer4.html b/doc/html/boost_asio/tutorial/tuttimer4.html deleted file mode 100644 index 603eeb9865..0000000000 --- a/doc/html/boost_asio/tutorial/tuttimer4.html +++ /dev/null @@ -1,151 +0,0 @@ -<html> -<head> -<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> -<title>Timer.4 - Using a member function as a handler</title> -<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css"> -<meta name="generator" content="DocBook XSL Stylesheets V1.78.1"> -<link rel="home" href="../../boost_asio.html" title="Boost.Asio"> -<link rel="up" href="../tutorial.html" title="Tutorial"> -<link rel="prev" href="tuttimer3/src.html" title="Source listing for Timer.3"> -<link rel="next" href="tuttimer4/src.html" title="Source listing for Timer.4"> -</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="tuttimer3/src.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../tutorial.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="tuttimer4/src.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> -</div> -<div class="section"> -<div class="titlepage"><div><div><h3 class="title"> -<a name="boost_asio.tutorial.tuttimer4"></a><a class="link" href="tuttimer4.html" title="Timer.4 - Using a member function as a handler">Timer.4 - Using a member - function as a handler</a> -</h3></div></div></div> -<p> - In this tutorial we will see how to use a class member function as a callback - handler. The program should execute identically to the tutorial program from - tutorial Timer.3. - </p> -<pre class="programlisting"><span class="special">#</span><span class="identifier">include</span> <span class="special"><</span><span class="identifier">iostream</span><span class="special">></span> -<span class="special">#</span><span class="identifier">include</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">hpp</span><span class="special">></span> -<span class="special">#</span><span class="identifier">include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">bind</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> -<span class="special">#</span><span class="identifier">include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">date_time</span><span class="special">/</span><span class="identifier">posix_time</span><span class="special">/</span><span class="identifier">posix_time</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span> -</pre> -<p> - Instead of defining a free function <code class="computeroutput"><span class="identifier">print</span></code> - as the callback handler, as we did in the earlier tutorial programs, we now - define a class called <code class="computeroutput"><span class="identifier">printer</span></code>. - </p> -<pre class="programlisting"><span class="keyword">class</span> <span class="identifier">printer</span> -<span class="special">{</span> -<span class="keyword">public</span><span class="special">:</span> -</pre> -<p> - The constructor of this class will take a reference to the io_service object - and use it when initialising the <code class="computeroutput"><span class="identifier">timer_</span></code> - member. The counter used to shut down the program is now also a member of - the class. - </p> -<pre class="programlisting"> <span class="identifier">printer</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">io_service</span><span class="special">&</span> <span class="identifier">io</span><span class="special">)</span> - <span class="special">:</span> <span class="identifier">timer_</span><span class="special">(</span><span class="identifier">io</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">posix_time</span><span class="special">::</span><span class="identifier">seconds</span><span class="special">(</span><span class="number">1</span><span class="special">)),</span> - <span class="identifier">count_</span><span class="special">(</span><span class="number">0</span><span class="special">)</span> - <span class="special">{</span> -</pre> -<p> - The boost::bind() function works just as well with class member functions - as with free functions. Since all non-static class member functions have - an implicit <code class="computeroutput"><span class="keyword">this</span></code> parameter, - we need to bind <code class="computeroutput"><span class="keyword">this</span></code> to the - function. As in tutorial Timer.3, boost::bind() converts our callback handler - (now a member function) into a function object that can be invoked as though - it has the signature <code class="computeroutput"><span class="keyword">void</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></code>. - </p> -<p> - You will note that the boost::asio::placeholders::error placeholder is not - specified here, as the <code class="computeroutput"><span class="identifier">print</span></code> - member function does not accept an error object as a parameter. - </p> -<pre class="programlisting"> <span class="identifier">timer_</span><span class="special">.</span><span class="identifier">async_wait</span><span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">bind</span><span class="special">(&</span><span class="identifier">printer</span><span class="special">::</span><span class="identifier">print</span><span class="special">,</span> <span class="keyword">this</span><span class="special">));</span> - <span class="special">}</span> -</pre> -<p> - In the class destructor we will print out the final value of the counter. - </p> -<pre class="programlisting"> <span class="special">~</span><span class="identifier">printer</span><span class="special">()</span> - <span class="special">{</span> - <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"Final count is "</span> <span class="special"><<</span> <span class="identifier">count_</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> - <span class="special">}</span> -</pre> -<p> - The <code class="computeroutput"><span class="identifier">print</span></code> member function - is very similar to the <code class="computeroutput"><span class="identifier">print</span></code> - function from tutorial Timer.3, except that it now operates on the class - data members instead of having the timer and counter passed in as parameters. - </p> -<pre class="programlisting"> <span class="keyword">void</span> <span class="identifier">print</span><span class="special">()</span> - <span class="special">{</span> - <span class="keyword">if</span> <span class="special">(</span><span class="identifier">count_</span> <span class="special"><</span> <span class="number">5</span><span class="special">)</span> - <span class="special">{</span> - <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">count_</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> - <span class="special">++</span><span class="identifier">count_</span><span class="special">;</span> - - <span class="identifier">timer_</span><span class="special">.</span><span class="identifier">expires_at</span><span class="special">(</span><span class="identifier">timer_</span><span class="special">.</span><span class="identifier">expires_at</span><span class="special">()</span> <span class="special">+</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">posix_time</span><span class="special">::</span><span class="identifier">seconds</span><span class="special">(</span><span class="number">1</span><span class="special">));</span> - <span class="identifier">timer_</span><span class="special">.</span><span class="identifier">async_wait</span><span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">bind</span><span class="special">(&</span><span class="identifier">printer</span><span class="special">::</span><span class="identifier">print</span><span class="special">,</span> <span class="keyword">this</span><span class="special">));</span> - <span class="special">}</span> - <span class="special">}</span> - -<span class="keyword">private</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">deadline_timer</span> <span class="identifier">timer_</span><span class="special">;</span> - <span class="keyword">int</span> <span class="identifier">count_</span><span class="special">;</span> -<span class="special">};</span> -</pre> -<p> - The <code class="computeroutput"><span class="identifier">main</span></code> function is much - simpler than before, as it now declares a local <code class="computeroutput"><span class="identifier">printer</span></code> - object before running the io_service as normal. - </p> -<pre class="programlisting"><span class="keyword">int</span> <span class="identifier">main</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">io_service</span> <span class="identifier">io</span><span class="special">;</span> - <span class="identifier">printer</span> <span class="identifier">p</span><span class="special">(</span><span class="identifier">io</span><span class="special">);</span> - <span class="identifier">io</span><span class="special">.</span><span class="identifier">run</span><span class="special">();</span> - - <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span> -<span class="special">}</span> -</pre> -<p> - See the <a class="link" href="tuttimer4/src.html" title="Source listing for Timer.4">full source listing</a> - </p> -<p> - Return to the <a class="link" href="../tutorial.html" title="Tutorial">tutorial index</a> - </p> -<p> - Previous: <a class="link" href="tuttimer3.html" title="Timer.3 - Binding arguments to a handler">Timer.3 - Binding - arguments to a handler</a> - </p> -<p> - Next: <a class="link" href="tuttimer5.html" title="Timer.5 - Synchronising handlers in multithreaded programs">Timer.5 - Synchronising - handlers in multithreaded programs</a> - </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 © 2003-2015 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="tuttimer3/src.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../tutorial.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="tuttimer4/src.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> -</div> -</body> -</html> |