<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> <title>io_service::dispatch</title> <link rel="stylesheet" href="../../../boostbook.css" type="text/css"> <meta name="generator" content="DocBook XSL Stylesheets V1.73.2"> <link rel="start" href="../../../index.html" title="Asio"> <link rel="up" href="../io_service.html" title="io_service"> <link rel="prev" href="add_service.html" title="io_service::add_service"> <link rel="next" href="has_service.html" title="io_service::has_service"> </head> <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> <table cellpadding="2" width="100%"><tr><td valign="top"><img alt="asio C++ library" width="250" height="60" src="../../../asio.png"></td></tr></table> <hr> <div class="spirit-nav"> <a accesskey="p" href="add_service.html"><img src="../../../prev.png" alt="Prev"></a><a accesskey="u" href="../io_service.html"><img src="../../../up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../home.png" alt="Home"></a><a accesskey="n" href="has_service.html"><img src="../../../next.png" alt="Next"></a> </div> <div class="section" lang="en"> <div class="titlepage"><div><div><h4 class="title"> <a name="asio.reference.io_service.dispatch"></a><a class="link" href="dispatch.html" title="io_service::dispatch"> io_service::dispatch</a> </h4></div></div></div> <p> <a class="indexterm" name="id842995"></a> Request the <a class="link" href="../io_service.html" title="io_service"><code class="computeroutput"><span class="identifier">io_service</span></code></a> to invoke the given handler. </p> <pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> <span class="keyword">typename</span> <a class="link" href="../CompletionHandler.html" title="Completion handler requirements">CompletionHandler</a><span class="special">></span> <span class="keyword">void</span> <span class="identifier">dispatch</span><span class="special">(</span> <span class="identifier">CompletionHandler</span> <span class="identifier">handler</span><span class="special">);</span> </pre> <p> This function is used to ask the <a class="link" href="../io_service.html" title="io_service"><code class="computeroutput"><span class="identifier">io_service</span></code></a> to execute the given handler. </p> <p> The <a class="link" href="../io_service.html" title="io_service"><code class="computeroutput"><span class="identifier">io_service</span></code></a> guarantees that the handler will only be called in a thread in which the <code class="computeroutput"><span class="identifier">run</span><span class="special">()</span></code>, <code class="computeroutput"><span class="identifier">run_one</span><span class="special">()</span></code>, <code class="computeroutput"><span class="identifier">poll</span><span class="special">()</span></code> or <code class="computeroutput"><span class="identifier">poll_one</span><span class="special">()</span></code> member functions is currently being invoked. The handler may be executed inside this function if the guarantee can be met. </p> <a name="asio.reference.io_service.dispatch.parameters"></a><h6> <a name="id843192"></a> <a class="link" href="dispatch.html#asio.reference.io_service.dispatch.parameters">Parameters</a> </h6> <div class="variablelist"> <p class="title"><b></b></p> <dl> <dt><span class="term">handler</span></dt> <dd> <p> The handler to be called. The <a class="link" href="../io_service.html" title="io_service"><code class="computeroutput"><span class="identifier">io_service</span></code></a> will make a copy of the handler object 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> </pre> <p> </p> </dd> </dl> </div> <a name="asio.reference.io_service.dispatch.remarks"></a><h6> <a name="id843267"></a> <a class="link" href="dispatch.html#asio.reference.io_service.dispatch.remarks">Remarks</a> </h6> <p> This function throws an exception only if: </p> <div class="itemizedlist"><ul type="disc"> <li> the handler's <code class="computeroutput"><span class="identifier">asio_handler_allocate</span></code> function; or </li> <li> the handler's copy constructor </li> </ul></div> <p> throws an exception. </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 - 2010 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="add_service.html"><img src="../../../prev.png" alt="Prev"></a><a accesskey="u" href="../io_service.html"><img src="../../../up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../home.png" alt="Home"></a><a accesskey="n" href="has_service.html"><img src="../../../next.png" alt="Next"></a> </div> </body> </html>