klarkxy/hustoj
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
aceaaeb27215be26ade6a73ee1d13970b5344668
hustoj/web/cppreference-zh/chmhelp/cpp-thread-condition_variable-notify_one.html
klarkxy 196e706fe4 上传cppreference
2025-08-01 12:57:54 +08:00

122 lines
12 KiB
HTML
Raw Blame History

<!DOCTYPE html>
<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
<head><meta http-equiv="x-ua-compatible" content="ie=edge">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>std::condition_variable::notify_one</title>
<link rel="stylesheet" href="ext.css" />
<link rel="stylesheet" href="site_modules.css" />
</head>
<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_thread_condition_variable_notify_one skin-cppreference2 action-view cpp-page-template cpp-navbar">
<div id="cpp-content-base">
<div id="content"><a id="top"></a>
<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::condition_variable::</span>notify_one</h1>
<div id="bodyContent">
<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-thread.html">thread</a>&lrm; | <a href="cpp-thread-condition_variable.html">condition variable</a></span></div>
<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
<div class="t-page-template" style="">
<p></p>
</div>
<table class="t-dcl-begin">
<tbody>
<tr class="t-dcl t-since-cxx11">
<td>
<div><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span> notify_one<span class="br0">(</span><span class="br0">)</span> <span class="kw1">noexcept</span><span class="sy4">;</span></span></div>
</td>
<td class="t-dcl-nopad"></td>
<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
</tr>
<tr class="t-dcl-sep">
<td></td>
<td></td>
<td></td>
</tr>
</tbody>
</table>
<p>&#33509;&#20219;&#20309;&#32447;&#31243;&#22312; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="sy2">*</span>this</span></span> &#19978;&#31561;&#24453;&#65292;&#21017;&#35843;&#29992; <code>notify_one</code> &#20250;&#35299;&#38459;&#22622;&#31561;&#24453;&#32447;&#31243;&#20043;&#19968;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
<p>&#65288;&#26080;&#65289;</p>
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<p>&#65288;&#26080;&#65289;</p>
<h3><span class="mw-headline" id=".E6.B3.A8.E6.84.8F">&#27880;&#24847;</span></h3>
<p><code>notify_one()</code>/<code>notify_all()</code> &#30340;&#25928;&#26524;&#19982; <code>wait()</code>/<code>wait_for()</code>/<code>wait_until()</code> &#30340;&#19977;&#20010;&#21407;&#23376;&#37096;&#20998;&#30340;&#27599;&#19968;&#32773;&#65288;&#35299;&#38145;+&#31561;&#24453;&#12289;&#21796;&#37266;&#21644;&#38145;&#23450;&#65289;&#20197;&#33021;&#30475;&#20570;&#21407;&#23376;&#21464;&#37327;<a href="cpp-atomic-memory_order.html#.E4.BF.AE.E6.94.B9.E9.A1.BA.E5.BA.8F">&#20462;&#25913;&#39034;&#24207;</a>&#21333;&#29420;&#20840;&#24207;&#21457;&#29983;&#65306;&#39034;&#24207;&#23545;&#27492;&#21333;&#29420;&#30340; condition_variable &#26159;&#29305;&#23450;&#30340;&#12290;&#35692;&#22914;&#65292;&#36825;&#20351;&#24471; <code>notify_one()</code> &#19981;&#21487;&#33021;&#34987;&#24310;&#36831;&#24182;&#35299;&#38145;&#27491;&#22909;&#22312;&#36827;&#34892; <code>notify_one()</code> &#35843;&#29992;&#21518;&#24320;&#22987;&#31561;&#24453;&#30340;&#32447;&#31243;&#12290;</p>
<p>&#36890;&#30693;&#32447;&#31243;&#19981;&#24517;&#20445;&#26377;&#31561;&#24453;&#32447;&#31243;&#25152;&#20445;&#26377;&#30340;&#21516;&#19968;&#20114;&#26021;&#19978;&#30340;&#38145;&#65307;&#23454;&#38469;&#19978;&#36825;&#20040;&#20570;&#26159;&#21155;&#21270;&#65292;&#22240;&#20026;&#34987;&#36890;&#30693;&#32447;&#31243;&#23558;&#31435;&#21363;&#20877;&#27425;&#38459;&#22622;&#65292;&#31561;&#24453;&#36890;&#30693;&#32447;&#31243;&#37322;&#25918;&#38145;&#12290;&#28982;&#32780;&#19968;&#20123;&#23454;&#29616;&#65288;&#23588;&#20854;&#26159;&#35768;&#22810; pthread &#30340;&#23454;&#29616;&#65289;&#36776;&#35782;&#27492;&#24773;&#24418;&#65292;&#22312;&#36890;&#30693;&#35843;&#29992;&#20013;&#65292;&#30452;&#25509;&#20174;&#26465;&#20214;&#21464;&#37327;&#38431;&#21015;&#36716;&#31227;&#31561;&#24453;&#32447;&#31243;&#21040;&#20114;&#26021;&#38431;&#21015;&#65292;&#32780;&#19981;&#21796;&#37266;&#23427;&#65292;&#20197;&#36991;&#20813;&#27492;&ldquo;&#24613;&#20419;&#24182;&#31561;&#24453;&rdquo;&#22330;&#26223;&#12290;</p>
<p>&#28982;&#32780;&#65292;&#22312;&#35201;&#27714;&#31934;&#30830;&#35843;&#24230;&#20107;&#20214;&#26102;&#65292;&#21487;&#33021;&#24517;&#39035;&#22312;&#22788;&#20110;&#38145;&#19979;&#26102;&#36890;&#30693;&#65292;&#20363;&#22914;&#65292;&#22312;&#33509;&#28385;&#36275;&#26465;&#20214;&#21017;&#32447;&#31243;&#23558;&#36864;&#20986;&#31243;&#24207;&#65292;&#23548;&#33268;&#26512;&#26500;&#36890;&#30693;&#32447;&#31243;&#30340; condition_variable &#30340;&#24773;&#20917;&#19979;&#12290;&#20114;&#26021;&#35299;&#38145;&#20043;&#21518;&#65292;&#20294;&#22312;&#36890;&#30693;&#21069;&#30340;&#34394;&#20551;&#21796;&#37266;&#21487;&#33021;&#23548;&#33268;&#36890;&#30693;&#22312;&#34987;&#38144;&#27585;&#23545;&#35937;&#19978;&#35843;&#29992;&#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
<div class="t-example">
<div class="t-example-live-link"></div>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="cpp source-cpp">
<pre class="de1"><span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;condition_variable&gt;</span>
<span class="co2">#include &lt;thread&gt;</span>
<span class="co2">#include &lt;chrono&gt;</span>
<a href="cpp-thread-condition_variable.html"><span class="kw2171">std::<span class="me2">condition_variable</span></span></a> cv<span class="sy4">;</span>
<a href="cpp-thread-mutex.html"><span class="kw2154">std::<span class="me2">mutex</span></span></a> cv_m<span class="sy4">;</span>
<span class="kw4">int</span> i <span class="sy1">=</span> <span class="nu0">0</span><span class="sy4">;</span>
<span class="kw4">bool</span> done <span class="sy1">=</span> <span class="kw2">false</span><span class="sy4">;</span>
<span class="kw4">void</span> waits<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-thread-unique_lock.html"><span class="kw2167">std::<span class="me2">unique_lock</span></span></a><span class="sy1">&lt;</span><a href="cpp-thread-mutex.html"><span class="kw2154">std::<span class="me2">mutex</span></span></a><span class="sy1">&gt;</span> lk<span class="br0">(</span>cv_m<span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;Waiting... <span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
cv.<span class="me1">wait</span><span class="br0">(</span>lk, <span class="br0">[</span><span class="br0">]</span><span class="br0">{</span><span class="kw1">return</span> i <span class="sy1">==</span> <span class="nu0">1</span><span class="sy4">;</span><span class="br0">}</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;...finished waiting. i == 1<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
done <span class="sy1">=</span> <span class="kw2">true</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw4">void</span> signals<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-thread-sleep_for.html"><span class="kw2149">std::<span class="me2">this_thread</span><span class="sy4">::</span><span class="me2">sleep_for</span></span></a><span class="br0">(</span><a href="cpp-chrono-duration.html"><span class="kw997">std::<span class="me2">chrono</span><span class="sy4">::</span><span class="me2">seconds</span></span></a><span class="br0">(</span><span class="nu0">1</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;Notifying falsely...<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
cv.<span class="me1">notify_one</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#31561;&#24453;&#32447;&#31243;&#34987;&#36890;&#30693; i == 0.</span>
<span class="co1">// cv.wait &#21796;&#37266;&#65292;&#26816;&#26597; i &#65292;&#20877;&#22238;&#21040;&#31561;&#24453;</span>
<a href="cpp-thread-unique_lock.html"><span class="kw2167">std::<span class="me2">unique_lock</span></span></a><span class="sy1">&lt;</span><a href="cpp-thread-mutex.html"><span class="kw2154">std::<span class="me2">mutex</span></span></a><span class="sy1">&gt;</span> lk<span class="br0">(</span>cv_m<span class="br0">)</span><span class="sy4">;</span>
i <span class="sy1">=</span> <span class="nu0">1</span><span class="sy4">;</span>
<span class="kw1">while</span> <span class="br0">(</span><span class="sy3">!</span>done<span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;Notifying true change...<span class="es1">\n</span>&quot;</span><span class="sy4">;</span>
lk.<span class="me1">unlock</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
cv.<span class="me1">notify_one</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#31561;&#24453;&#32447;&#31243;&#34987;&#36890;&#30693; i == 1 &#65292; cv.wait &#36820;&#22238;</span>
<a href="cpp-thread-sleep_for.html"><span class="kw2149">std::<span class="me2">this_thread</span><span class="sy4">::</span><span class="me2">sleep_for</span></span></a><span class="br0">(</span><a href="cpp-chrono-duration.html"><span class="kw997">std::<span class="me2">chrono</span><span class="sy4">::</span><span class="me2">seconds</span></span></a><span class="br0">(</span><span class="nu0">1</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
lk.<span class="me1">lock</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="br0">}</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-thread-thread.html"><span class="kw2146">std::<span class="me2">thread</span></span></a> t1<span class="br0">(</span>waits<span class="br0">)</span>, t2<span class="br0">(</span>signals<span class="br0">)</span><span class="sy4">;</span>
t1.<span class="me1">join</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
t2.<span class="me1">join</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
</div>
<p>&#21487;&#33021;&#30340;&#36755;&#20986;&#65306;</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="text source-text">
<pre class="de1">Waiting...
Notifying falsely...
Notifying true change...
...finished waiting. i == 1</pre></div>
</div>
</div>
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
<table class="t-dsc-begin">
<tr class="t-dsc">
<td>
<div class="t-dsc-member-div">
<div><a href="cpp-thread-condition_variable-notify_all.html"><span class="t-lines"><span>notify_all</span></span></a></div>
</div>
</td>
<td>&#36890;&#30693;&#25152;&#26377;&#31561;&#24453;&#30340;&#32447;&#31243;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
</tr>
</table>
</div>
<div class="visualClear"></div>
</div>
</div>
</div>
</body>
</html>
Reference in New Issue View Git Blame Copy Permalink