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<title>std::unique_lock&lt;Mutex&gt;::lock</title>
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::unique_lock&lt;Mutex&gt;::</span>lock</h1>
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<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-unique_lock.html">unique lock</a></span></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span> lock<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span></span></div>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<p>&#38145;&#23450;&#20851;&#32852;&#20114;&#26021;&#12290;&#31561;&#25928;&#22320;&#35843;&#29992; <span class="t-c"><span class="mw-geshi cpp source-cpp">mutex<span class="br0">(</span><span class="br0">)</span><span class="sy2">-</span><span class="sy1">&gt;</span>lock<span class="br0">(</span><span class="br0">)</span></span></span> &#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=".E5.BC.82.E5.B8.B8">&#24322;&#24120;</span></h3>
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<li>&#20219;&#20309; <span class="t-c"><span class="mw-geshi cpp source-cpp">mutex<span class="br0">(</span><span class="br0">)</span><span class="sy2">-</span><span class="sy1">&gt;</span>lock<span class="br0">(</span><span class="br0">)</span></span></span> &#25152;&#25243;&#30340;&#24322;&#24120;</li>
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<li>&#33509;&#26080;&#20851;&#32852;&#20114;&#26021;&#65292;&#21017;&#20026;&#20197; <span class="t-lc"><a href="cpp-error-errc.html">std::errc::operation_not_permitted</a></span> &#20026;&#38169;&#35823;&#30721;&#30340; <span class="t-lc"><a href="cpp-error-system_error.html">std::system_error</a></span></li>
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<li>&#33509;&#20851;&#32852;&#20114;&#26021;&#24050;&#20026;&#27492; <code>unique_lock</code> &#25152;&#38145;&#23450;&#65288;&#25442;&#35328;&#20043;&#65292; <a href="cpp-thread-unique_lock-owns_lock.html">owns_lock</a> &#20026; true &#65289;&#65292;&#21017;&#20026;&#20197; <span class="t-lc"><a href="cpp-error-errc.html">std::errc::resource_deadlock_would_occur</a></span> &#20026;&#38169;&#35823;&#30721;&#30340; <span class="t-lc"><a href="cpp-error-system_error.html">std::system_error</a></span></li>
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<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
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<p>&#19979;&#21015;&#31034;&#20363;&#29992; <code>lock</code> &#37325;&#33719;&#24471;&#34987;&#35299;&#38145;&#30340;&#20114;&#26021;&#12290;</p>
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<pre class="de1"><span class="co2">#include &lt;mutex&gt;</span>
<span class="co2">#include &lt;thread&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;vector&gt;</span>
<span class="co2">#include &lt;chrono&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<span class="kw4">int</span> counter <span class="sy1">=</span> <span class="nu0">0</span><span class="sy4">;</span>
<a href="cpp-thread-mutex.html"><span class="kw2154">std::<span class="me2">mutex</span></span></a> counter_mutex<span class="sy4">;</span>
<a href="cpp-container-vector.html"><span class="kw1269">std::<span class="me2">vector</span></span></a><span class="sy1">&lt;</span><a href="cpp-thread-thread.html"><span class="kw2146">std::<span class="me2">thread</span></span></a><span class="sy1">&gt;</span> threads<span class="sy4">;</span>
<span class="kw4">auto</span> worker_task <span class="sy1">=</span> <span class="br0">[</span><span class="sy3">&amp;</span><span class="br0">]</span><span class="br0">(</span><span class="kw4">int</span> id<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> lock<span class="br0">(</span>counter_mutex<span class="br0">)</span><span class="sy4">;</span>
<span class="sy2">++</span>counter<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> id <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;, initial counter: &quot;</span> <span class="sy1">&lt;&lt;</span> counter <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
lock.<span class="me1">unlock</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// &#25105;&#20204;&#27169;&#25311;&#26114;&#36149;&#25805;&#20316;&#26102;&#19981;&#20445;&#26377;&#38145;</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>
lock.<span class="me1">lock</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
<span class="sy2">++</span>counter<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> id <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;, final counter: &quot;</span> <span class="sy1">&lt;&lt;</span> counter <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="br0">}</span><span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">int</span> i <span class="sy1">=</span> <span class="nu0">0</span><span class="sy4">;</span> i <span class="sy1">&lt;</span> <span class="nu0">10</span><span class="sy4">;</span> <span class="sy2">++</span>i<span class="br0">)</span> threads.<span class="me1">emplace_back</span><span class="br0">(</span>worker_task, i<span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">auto</span> <span class="sy3">&amp;</span>thread <span class="sy4">:</span> threads<span class="br0">)</span> thread.<span class="me1">join</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
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<p>&#21487;&#33021;&#30340;&#36755;&#20986;&#65306;</p>
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<pre class="de1">0, initial counter: 1
1, initial counter: 2
2, initial counter: 3
3, initial counter: 4
4, initial counter: 5
5, initial counter: 6
6, initial counter: 7
7, initial counter: 8
8, initial counter: 9
9, initial counter: 10
6, final counter: 11
3, final counter: 12
4, final counter: 13
2, final counter: 14
5, final counter: 15
0, final counter: 16
1, final counter: 17
7, final counter: 18
9, final counter: 19
8, final counter: 20</pre></div>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
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<div><a href="cpp-thread-unique_lock-try_lock.html"><span class="t-lines"><span>try_lock</span></span></a></div>
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<td>&#23581;&#35797;&#38145;&#23450;&#20851;&#32852;&#20114;&#26021;&#65292;&#33509;&#20114;&#26021;&#19981;&#21487;&#29992;&#21017;&#36820;&#22238;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><a href="cpp-thread-unique_lock-unlock.html"><span class="t-lines"><span>unlock</span></span></a></div>
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<td>&#35299;&#38145;&#20851;&#32852;&#20114;&#26021;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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