1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>io_context::run (2 of 2 overloads)</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="../../../../boost_asio.html" title="Boost.Asio"> 8<link rel="up" href="../run.html" title="io_context::run"> 9<link rel="prev" href="overload1.html" title="io_context::run (1 of 2 overloads)"> 10<link rel="next" href="../run_for.html" title="io_context::run_for"> 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="overload1.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../run.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="../run_for.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h5 class="title"> 27<a name="boost_asio.reference.io_context.run.overload2"></a><a class="link" href="overload2.html" title="io_context::run (2 of 2 overloads)">io_context::run 28 (2 of 2 overloads)</a> 29</h5></div></div></div> 30<p> 31 (Deprecated: Use non-error_code overload.) Run the <a class="link" href="../../io_context.html" title="io_context"><code class="computeroutput">io_context</code></a> 32 object's event processing loop. 33 </p> 34<pre class="programlisting">count_type run( 35 boost::system::error_code & ec); 36</pre> 37<p> 38 The <code class="computeroutput">run()</code> function blocks until all work has finished and 39 there are no more handlers to be dispatched, or until the <a class="link" href="../../io_context.html" title="io_context"><code class="computeroutput">io_context</code></a> 40 has been stopped. 41 </p> 42<p> 43 Multiple threads may call the <code class="computeroutput">run()</code> function to set up a 44 pool of threads from which the <a class="link" href="../../io_context.html" title="io_context"><code class="computeroutput">io_context</code></a> 45 may execute handlers. All threads that are waiting in the pool are equivalent 46 and the <a class="link" href="../../io_context.html" title="io_context"><code class="computeroutput">io_context</code></a> 47 may choose any one of them to invoke a handler. 48 </p> 49<p> 50 A normal exit from the <code class="computeroutput">run()</code> function implies that the 51 <a class="link" href="../../io_context.html" title="io_context"><code class="computeroutput">io_context</code></a> 52 object is stopped (the <code class="computeroutput">stopped()</code> function returns <code class="computeroutput">true</code>). 53 Subsequent calls to <code class="computeroutput">run()</code>, <code class="computeroutput">run_one()</code>, <code class="computeroutput">poll()</code> 54 or <code class="computeroutput">poll_one()</code> will return immediately unless there is a 55 prior call to <code class="computeroutput">restart()</code>. 56 </p> 57<h6> 58<a name="boost_asio.reference.io_context.run.overload2.h0"></a> 59 <span class="phrase"><a name="boost_asio.reference.io_context.run.overload2.parameters"></a></span><a class="link" href="overload2.html#boost_asio.reference.io_context.run.overload2.parameters">Parameters</a> 60 </h6> 61<div class="variablelist"> 62<p class="title"><b></b></p> 63<dl class="variablelist"> 64<dt><span class="term">ec</span></dt> 65<dd><p> 66 Set to indicate what error occurred, if any. 67 </p></dd> 68</dl> 69</div> 70<h6> 71<a name="boost_asio.reference.io_context.run.overload2.h1"></a> 72 <span class="phrase"><a name="boost_asio.reference.io_context.run.overload2.return_value"></a></span><a class="link" href="overload2.html#boost_asio.reference.io_context.run.overload2.return_value">Return 73 Value</a> 74 </h6> 75<p> 76 The number of handlers that were executed. 77 </p> 78<h6> 79<a name="boost_asio.reference.io_context.run.overload2.h2"></a> 80 <span class="phrase"><a name="boost_asio.reference.io_context.run.overload2.remarks"></a></span><a class="link" href="overload2.html#boost_asio.reference.io_context.run.overload2.remarks">Remarks</a> 81 </h6> 82<p> 83 Calling the <code class="computeroutput">run()</code> function from a thread that is currently 84 calling one of <code class="computeroutput">run()</code>, <code class="computeroutput">run_one()</code>, <code class="computeroutput">run_for()</code>, 85 <code class="computeroutput">run_until()</code>, <code class="computeroutput">poll()</code> or <code class="computeroutput">poll_one()</code> 86 on the same <a class="link" href="../../io_context.html" title="io_context"><code class="computeroutput">io_context</code></a> 87 object may introduce the potential for deadlock. It is the caller's reponsibility 88 to avoid this. 89 </p> 90<p> 91 The <code class="computeroutput">poll()</code> function may also be used to dispatch ready handlers, 92 but without blocking. 93 </p> 94</div> 95<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 96<td align="left"></td> 97<td align="right"><div class="copyright-footer">Copyright © 2003-2020 Christopher M. 98 Kohlhoff<p> 99 Distributed under the Boost Software License, Version 1.0. (See accompanying 100 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>) 101 </p> 102</div></td> 103</tr></table> 104<hr> 105<div class="spirit-nav"> 106<a accesskey="p" href="overload1.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../run.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="../run_for.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 107</div> 108</body> 109</html> 110