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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>shared_future</h1>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-future.html">&lt;future&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> T <span class="sy1">&gt;</span> <span class="kw1">class</span> shared_future<span class="sy4">;</span></span></div>
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<td>(1)</td>
<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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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> T <span class="sy1">&gt;</span> <span class="kw1">class</span> shared_future<span class="sy1">&lt;</span>T<span class="sy3">&amp;</span><span class="sy1">&gt;</span><span class="sy4">;</span></span></div>
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<td>(2)</td>
<td><span class="t-mark-rev t-since-cxx11">(C++11 &#36215;)</span></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1">&lt;&gt;</span> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<span class="kw1">class</span> shared_future<span class="sy1">&lt;</span><span class="kw4">void</span><span class="sy1">&gt;</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>&#31867;&#27169;&#26495; <code>std::shared_future</code> &#25552;&#20379;&#35775;&#38382;&#24322;&#27493;&#25805;&#20316;&#32467;&#26524;&#30340;&#26426;&#21046;&#65292;&#31867;&#20284; <span class="t-lc"><a href="cpp-thread-future.html">std::future</a></span> &#65292;&#38500;&#20102;&#20801;&#35768;&#22810;&#20010;&#32447;&#31243;&#31561;&#20505;&#21516;&#19968;&#20849;&#20139;&#29366;&#24577;&#12290;&#19981;&#21516;&#20110;&#20165;&#21487;&#31227;&#21160;&#30340; <span class="t-lc"><a href="cpp-thread-future.html">std::future</a></span> &#65288;&#25925;&#21482;&#26377;&#19968;&#20010;&#23454;&#20363;&#33021;&#25351;&#20195;&#20219;&#20309;&#29305;&#23450;&#30340;&#24322;&#27493;&#32467;&#26524;&#65289;&#65292;<code>std::shared_future</code> &#21487;&#22797;&#21046;&#32780;&#19988;&#22810;&#20010; shared_future &#23545;&#35937;&#33021;&#25351;&#20195;&#21516;&#19968;&#20849;&#20139;&#29366;&#24577;&#12290;</p>
<p>&#33509;&#27599;&#20010;&#32447;&#31243;&#36890;&#36807;&#20854;&#33258;&#36523;&#30340; <code>shared_future</code> &#23545;&#35937;&#21103;&#26412;&#35775;&#38382;&#65292;&#21017;&#20174;&#22810;&#20010;&#32447;&#31243;&#35775;&#38382;&#21516;&#19968;&#20849;&#20139;&#29366;&#24577;&#26159;&#23433;&#20840;&#30340;&#12290;</p>
<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-shared_future-shared_future.html"><span class="t-lines"><span>(&#26500;&#36896;&#20989;&#25968;)</span></span></a></div>
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<td>&#26500;&#36896; future &#23545;&#35937;<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-shared_future-~shared_future.html"><span class="t-lines"><span>(&#26512;&#26500;&#20989;&#25968;)</span></span></a></div>
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<td>&#38144;&#27585;future&#23545;&#35937;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><a href="cpp-thread-shared_future-operator=.html"><span class="t-lines"><span>operator=</span></span></a></div>
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<td>&#36171;&#20540;&#20869;&#23481;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<h5><span class="mw-headline" id=".E8.8E.B7.E5.8F.96.E7.BB.93.E6.9E.9C">&#33719;&#21462;&#32467;&#26524;</span></h5>
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<div><a href="cpp-thread-shared_future-get.html"><span class="t-lines"><span>get</span></span></a></div>
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<td>&#36820;&#22238;&#32467;&#26524;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<h5><span class="mw-headline" id=".E7.8A.B6.E6.80.81">&#29366;&#24577;</span></h5>
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<div><a href="cpp-thread-shared_future-valid.html"><span class="t-lines"><span>valid</span></span></a></div>
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<td>&#26816;&#26597; future &#26159;&#21542;&#25317;&#26377;&#20849;&#20139;&#29366;&#24577;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><a href="cpp-thread-shared_future-wait.html"><span class="t-lines"><span>wait</span></span></a></div>
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<td>&#31561;&#24453;&#32467;&#26524;&#21464;&#24471;&#21487;&#29992;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><a href="cpp-thread-shared_future-wait_for.html"><span class="t-lines"><span>wait_for</span></span></a></div>
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<td>&#31561;&#24453;&#32467;&#26524;&#65292;&#22914;&#26524;&#22312;&#25351;&#23450;&#30340;&#36229;&#26102;&#38388;&#38548;&#21518;&#20173;&#28982;&#26080;&#27861;&#24471;&#21040;&#32467;&#26524;&#65292;&#21017;&#36820;&#22238;&#12290;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<div><a href="cpp-thread-shared_future-wait_until.html"><span class="t-lines"><span>wait_until</span></span></a></div>
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<td>&#31561;&#24453;&#32467;&#26524;&#65292;&#22914;&#26524;&#22312;&#24050;&#32463;&#21040;&#36798;&#25351;&#23450;&#30340;&#26102;&#38388;&#28857;&#26102;&#20173;&#28982;&#26080;&#27861;&#24471;&#21040;&#32467;&#26524;&#65292;&#21017;&#36820;&#22238;&#12290;<br />
<span class="t-mark">(&#20844;&#24320;&#25104;&#21592;&#20989;&#25968;)</span></td>
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<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
<div class="t-example">
<p><code>shared_future</code> &#21487;&#29992;&#20110;&#21516;&#26102;&#21521;&#22810;&#20010;&#32447;&#31243;&#21457;&#20449;&#65292;&#31867;&#20284; <span class="t-lc"><a href="cpp-thread-condition_variable-notify_all.html">std::condition_variable::notify_all()</a></span></p>
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<pre class="de1"><span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;future&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>
<a href="cpp-thread-promise.html"><span class="kw2179">std::<span class="me2">promise</span></span></a><span class="sy1">&lt;</span><span class="kw4">void</span><span class="sy1">&gt;</span> ready_promise, t1_ready_promise, t2_ready_promise<span class="sy4">;</span>
std<span class="sy4">::</span><span class="me2">shared_future</span><span class="sy1">&lt;</span><span class="kw4">void</span><span class="sy1">&gt;</span> ready_future<span class="br0">(</span>ready_promise.<span class="me1">get_future</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-chrono-time_point.html"><span class="kw991">std::<span class="me2">chrono</span><span class="sy4">::</span><span class="me2">time_point</span></span></a><span class="sy1">&lt;</span><a href="cpp-chrono-high_resolution_clock.html"><span class="kw1008">std::<span class="me2">chrono</span><span class="sy4">::</span><span class="me2">high_resolution_clock</span></span></a><span class="sy1">&gt;</span> start<span class="sy4">;</span>
<span class="kw4">auto</span> fun1 <span class="sy1">=</span> <span class="br0">[</span><span class="sy3">&amp;</span>, ready_future<span class="br0">]</span><span class="br0">(</span><span class="br0">)</span> <span class="sy2">-</span><span class="sy1">&gt;</span> <a href="cpp-chrono-duration.html"><span class="kw993">std::<span class="me2">chrono</span><span class="sy4">::</span><span class="me2">duration</span></span></a><span class="sy1">&lt;</span><span class="kw4">double</span>, <a href="cpp-numeric-ratio-ratio.html"><span class="kw1528">std::<span class="me2">milli</span></span></a><span class="sy1">&gt;</span>
<span class="br0">{</span>
t1_ready_promise.<span class="me1">set_value</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
ready_future.<span class="me1">wait</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#31561;&#24453;&#26469;&#33258; main() &#30340;&#20449;&#21495;</span>
<span class="kw1">return</span> std<span class="sy4">::</span><span class="me2">chrono</span><span class="sy4">::</span><span class="me2">high_resolution_clock</span><span class="sy4">::</span><span class="me2">now</span><span class="br0">(</span><span class="br0">)</span> <span class="sy2">-</span> start<span class="sy4">;</span>
<span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">auto</span> fun2 <span class="sy1">=</span> <span class="br0">[</span><span class="sy3">&amp;</span>, ready_future<span class="br0">]</span><span class="br0">(</span><span class="br0">)</span> <span class="sy2">-</span><span class="sy1">&gt;</span> <a href="cpp-chrono-duration.html"><span class="kw993">std::<span class="me2">chrono</span><span class="sy4">::</span><span class="me2">duration</span></span></a><span class="sy1">&lt;</span><span class="kw4">double</span>, <a href="cpp-numeric-ratio-ratio.html"><span class="kw1528">std::<span class="me2">milli</span></span></a><span class="sy1">&gt;</span>
<span class="br0">{</span>
t2_ready_promise.<span class="me1">set_value</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
ready_future.<span class="me1">wait</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span> <span class="co1">// &#31561;&#24453;&#26469;&#33258; main() &#30340;&#20449;&#21495;</span>
<span class="kw1">return</span> std<span class="sy4">::</span><span class="me2">chrono</span><span class="sy4">::</span><span class="me2">high_resolution_clock</span><span class="sy4">::</span><span class="me2">now</span><span class="br0">(</span><span class="br0">)</span> <span class="sy2">-</span> start<span class="sy4">;</span>
<span class="br0">}</span><span class="sy4">;</span>
<span class="kw4">auto</span> result1 <span class="sy1">=</span> <a href="cpp-thread-async.html"><span class="kw2183">std::<span class="me2">async</span></span></a><span class="br0">(</span><a href="cpp-thread-launch.html"><span class="kw2185">std::<span class="me2">launch</span><span class="sy4">::</span><span class="me2">async</span></span></a>, fun1<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">auto</span> result2 <span class="sy1">=</span> <a href="cpp-thread-async.html"><span class="kw2183">std::<span class="me2">async</span></span></a><span class="br0">(</span><a href="cpp-thread-launch.html"><span class="kw2185">std::<span class="me2">launch</span><span class="sy4">::</span><span class="me2">async</span></span></a>, fun2<span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// &#31561;&#24453;&#32447;&#31243;&#21464;&#20026;&#23601;&#32490;</span>
t1_ready_promise.<span class="me1">get_future</span><span class="br0">(</span><span class="br0">)</span>.<span class="me1">wait</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
t2_ready_promise.<span class="me1">get_future</span><span class="br0">(</span><span class="br0">)</span>.<span class="me1">wait</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// &#32447;&#31243;&#24050;&#23601;&#32490;&#65292;&#24320;&#22987;&#26102;&#38047;</span>
start <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">chrono</span><span class="sy4">::</span><span class="me2">high_resolution_clock</span><span class="sy4">::</span><span class="me2">now</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
<span class="co1">// &#21521;&#32447;&#31243;&#21457;&#20449;&#20351;&#20043;&#36816;&#34892;</span>
ready_promise.<span class="me1">set_value</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;Thread 1 received the signal &quot;</span>
<span class="sy1">&lt;&lt;</span> result1.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span>.<span class="me1">count</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot; ms after start<span class="es1">\n</span>&quot;</span>
<span class="sy1">&lt;&lt;</span> <span class="st0">&quot;Thread 2 received the signal &quot;</span>
<span class="sy1">&lt;&lt;</span> result2.<span class="me1">get</span><span class="br0">(</span><span class="br0">)</span>.<span class="me1">count</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot; ms after start<span class="es1">\n</span>&quot;</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">Thread 1 received the signal 0.072 ms after start
Thread 2 received the signal 0.041 ms after start</pre></div>
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