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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>lock_guard</h1>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-mutex.html">&lt;mutex&gt;</a></code></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;</span> <span class="kw1">class</span> Mutex <span class="sy1">&gt;</span><br />
<span class="kw1">class</span> lock_guard<span class="sy4">;</span></span></div>
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<p>&#31867; <code>lock_guard</code> &#26159;&#20114;&#26021;&#20307;&#21253;&#35013;&#22120;&#65292;&#20026;&#22312;&#20316;&#29992;&#22495;&#22359;&#26399;&#38388;&#21344;&#26377;&#20114;&#26021;&#25552;&#20379;&#20415;&#21033; <a href="cpp-language-raii.html">RAII &#39118;&#26684;</a>&#26426;&#21046;&#12290;</p>
<p>&#21019;&#24314; <code>lock_guard</code> &#23545;&#35937;&#26102;&#65292;&#23427;&#35797;&#22270;&#25509;&#25910;&#32473;&#23450;&#20114;&#26021;&#30340;&#25152;&#26377;&#26435;&#12290;&#25511;&#21046;&#31163;&#24320;&#21019;&#24314; <code>lock_guard</code> &#23545;&#35937;&#30340;&#20316;&#29992;&#22495;&#26102;&#65292;&#38144;&#27585; <code>lock_guard</code> &#24182;&#37322;&#25918;&#20114;&#26021;&#12290;</p>
<p><code>lock_guard</code> &#31867;&#19981;&#21487;&#22797;&#21046;&#12290;</p>
<h3><span class="mw-headline" id=".E6.A8.A1.E6.9D.BF.E5.BD.A2.E5.8F.82">&#27169;&#26495;&#24418;&#21442;</span></h3>
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<td>Mutex</td>
<td>-</td>
<td>&#35201;&#38145;&#23450;&#30340;&#20114;&#26021;&#12290;&#31867;&#22411;&#24517;&#39035;&#28385;&#36275;<a href="cpp-named_req-BasicLockable.html"><span style="font-style:italic">&#22522;&#26412;&#21487;&#38145;&#23450;</span> <span style="font-family: Georgia, &#39;DejaVu Serif&#39;, serif; font-style:italic">(BasicLockable)</span></a> &#35201;&#27714;</td>
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<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E7.B1.BB.E5.9E.8B">&#25104;&#21592;&#31867;&#22411;</span></h3>
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<td>&#25104;&#21592;&#31867;&#22411;</td>
<td>&#23450;&#20041;</td>
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<td><code>mutex_type</code></td>
<td>Mutex</td>
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<h3><span class="mw-headline" id=".E6.88.90.E5.91.98.E5.87.BD.E6.95.B0">&#25104;&#21592;&#20989;&#25968;</span></h3>
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<div><a href="cpp-thread-lock_guard-lock_guard.html"><span class="t-lines"><span>(&#26500;&#36896;&#20989;&#25968;)</span></span></a></div>
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<td>&#26500;&#36896; lock_guard &#65292;&#21487;&#36873;&#22320;&#38145;&#23450;&#32473;&#23450;&#30340;&#20114;&#26021;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div t-dsc-member-nobold-div">
<div><a href="cpp-thread-lock_guard-~lock_guard.html"><span class="t-lines"><span>(&#26512;&#26500;&#20989;&#25968;)</span></span></a></div>
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<td>&#26512;&#26500; lock_guard &#23545;&#35937;&#65292;&#35299;&#38145;&#24213;&#23618;&#20114;&#26021;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><span class="t-lines"><span>operator=</span></span></div>
<div><span class="t-lines"><span><span class="t-cmark">[&#34987;&#21024;&#38500;]</span></span></span></div>
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<td>&#19981;&#21487;&#22797;&#21046;&#36171;&#20540;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">&#27880;&#35299;</span></h3>
<p><a href="cpp-thread-scoped_lock.html"><tt>std::scoped_lock</tt></a> &#32473;&#20986; <code>lock_guard</code> &#30340;&#19968;&#31181;&#26367;&#20195;&#65292;&#29992;&#36991;&#20813;&#27515;&#38145;&#30340;&#31639;&#27861;&#25552;&#20379;&#38145;&#23450;&#22810;&#20010;&#20114;&#26021;&#20307;&#30340;&#33021;&#21147;&#12290;</p>
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<td><span class="t-mark-rev t-since-cxx17">(C++17 &#36215;)</span></td>
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<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
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<pre class="de1"><span class="co2">#include &lt;thread&gt;</span>
<span class="co2">#include &lt;mutex&gt;</span>
<span class="co2">#include &lt;iostream&gt;</span>
<span class="kw4">int</span> g_i <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> g_i_mutex<span class="sy4">;</span> <span class="co1">// &#20445;&#25252; g_i</span>
<span class="kw4">void</span> safe_increment<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
std<span class="sy4">::</span><span class="me2">lock_guard</span><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>g_i_mutex<span class="br0">)</span><span class="sy4">;</span>
<span class="sy2">++</span>g_i<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> <a href="cpp-thread-get_id.html"><span class="kw2148">std::<span class="me2">this_thread</span><span class="sy4">::</span><span class="me2">get_id</span></span></a><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;: &quot;</span> <span class="sy1">&lt;&lt;</span> g_i <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="co1">// g_i_mutex &#22312;&#38145;&#31163;&#24320;&#20316;&#29992;&#22495;&#26102;&#33258;&#21160;&#37322;&#25918;</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-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;main: &quot;</span> <span class="sy1">&lt;&lt;</span> g_i <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<a href="cpp-thread-thread.html"><span class="kw2146">std::<span class="me2">thread</span></span></a> t1<span class="br0">(</span>safe_increment<span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-thread-thread.html"><span class="kw2146">std::<span class="me2">thread</span></span></a> t2<span class="br0">(</span>safe_increment<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>
<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;main: &quot;</span> <span class="sy1">&lt;&lt;</span> g_i <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></pre></div>
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<p>&#21487;&#33021;&#30340;&#36755;&#20986;&#65306;</p>
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<pre class="de1">main: 0
140641306900224: 1
140641298507520: 2
main: 2</pre></div>
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<h3><span class="mw-headline" id=".E7.BC.BA.E9.99.B7.E6.8A.A5.E5.91.8A">&#32570;&#38519;&#25253;&#21578;</span></h3>
<p>&#19979;&#21015;&#26356;&#25913;&#34892;&#20026;&#30340;&#32570;&#38519;&#25253;&#21578;&#36861;&#28335;&#22320;&#24212;&#29992;&#20110;&#20197;&#21069;&#20986;&#29256;&#30340; C++ &#26631;&#20934;&#12290;</p>
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<th>DR</th>
<th>&#24212;&#29992;&#20110;</th>
<th>&#20986;&#29256;&#26102;&#30340;&#34892;&#20026;</th>
<th>&#27491;&#30830;&#34892;&#20026;</th>
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<td><a rel="nofollow" class="external text" href="https://cplusplus.github.io/LWG/issue2981">LWG 2981</a></td>
<td>C++17</td>
<td>&#26366;&#25552;&#20379;&#26469;&#33258; <code>lock_guard&lt;Mutex&gt;</code> &#30340;&#20887;&#20313;&#25512;&#23548;&#25351;&#24341;</td>
<td>&#24050;&#31227;&#38500;</td>
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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.html"><span class="t-lines"><span>unique_lock</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
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<td>&#23454;&#29616;&#21487;&#31227;&#21160;&#30340;&#20114;&#26021;&#20307;&#25152;&#26377;&#26435;&#21253;&#35013;&#22120;<br />
<span class="t-mark">(&#31867;&#27169;&#26495;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-thread-scoped_lock.html"><span class="t-lines"><span>scoped_lock</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
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<td>&#29992;&#20110;&#22810;&#20010;&#20114;&#26021;&#20307;&#30340;&#20813;&#27515;&#38145; RAII &#23553;&#35013;&#22120;<br />
<span class="t-mark">(&#31867;&#27169;&#26495;)</span></td>
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