279 lines
31 KiB
HTML
279 lines
31 KiB
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>atomic_...<span class="t-dsc-small"><std::shared_ptr></span></h1>
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<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-memory.html">memory</a>‎ | <a href="cpp-memory-shared_ptr.html">shared ptr</a></span></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br />
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<span class="kw4">bool</span> atomic_is_lock_free<span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> p <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td>(1)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 中弃用)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br />
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> atomic_load<span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> p <span class="br0">)</span><span class="sy4">;</span></span></div>
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</td>
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<td>(2)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 中弃用)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
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<p><a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> atomic_load_explicit<span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> p,<br /></p>
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<a href="cpp-atomic-memory_order.html"><span class="kw2092">std::<span class="me2">memory_order</span></span></a> mo <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(3)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 中弃用)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
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<p><span class="kw4">void</span> atomic_store<span class="br0">(</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> p,<br /></p>
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> r <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(4)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 中弃用)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
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<p><span class="kw4">void</span> atomic_store_explicit<span class="br0">(</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> p,<br />
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> r,<br /></p>
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<a href="cpp-atomic-memory_order.html"><span class="kw2092">std::<span class="me2">memory_order</span></span></a> mo<span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(5)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 中弃用)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
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<p><a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> atomic_exchange<span class="br0">(</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> p,<br /></p>
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> r<span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(6)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 中弃用)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T<span class="sy1">></span><br /></span>
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<p><a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> atomic_exchange_explicit<span class="br0">(</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> p,<br />
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> r,<br /></p>
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<a href="cpp-atomic-memory_order.html"><span class="kw2092">std::<span class="me2">memory_order</span></span></a> mo<span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(7)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 中弃用)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
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<p><span class="kw4">bool</span> atomic_compare_exchange_weak<span class="br0">(</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> p,<br />
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> expected,<br /></p>
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> desired<span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(8)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 中弃用)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> T<span class="sy1">></span><br /></span>
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<p><span class="kw4">bool</span> atomic_compare_exchange_strong<span class="br0">(</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> p,<br />
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> expected,<br /></p>
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> desired<span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(9)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 中弃用)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
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<p><span class="kw4">bool</span> atomic_compare_exchange_strong_explicit<span class="br0">(</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> p,<br />
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> expected,<br />
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> desired,<br />
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<a href="cpp-atomic-memory_order.html"><span class="kw2092">std::<span class="me2">memory_order</span></span></a> success,<br /></p>
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<a href="cpp-atomic-memory_order.html"><span class="kw2092">std::<span class="me2">memory_order</span></span></a> failure<span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(10)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 中弃用)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> T <span class="sy1">></span><br /></span>
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<p><span class="kw4">bool</span> atomic_compare_exchange_weak_explicit<span class="br0">(</span> <a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> p,<br />
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span><span class="sy2">*</span> expected,<br />
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<a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1"><</span>T<span class="sy1">></span> desired,<br />
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<a href="cpp-atomic-memory_order.html"><span class="kw2092">std::<span class="me2">memory_order</span></span></a> success,<br /></p>
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<a href="cpp-atomic-memory_order.html"><span class="kw2092">std::<span class="me2">memory_order</span></span></a> failure<span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(11)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 中弃用)</span></td>
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</tr>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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</tr>
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</tbody>
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</table>
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<p>若多个执行线程访问同一 <span class="t-lc"><a href="cpp-memory-shared_ptr.html">std::shared_ptr</a></span> 对象而无同步，且这些访问中任一者使用 <span class="t-lc">shared_ptr</span> 的非 const 成员函数，则发生数据竞争，除非所有这种访问都通过这些作为对应原子访问函数（ <span class="t-lc"><a href="cpp-atomic-atomic_load.html">std::atomic_load</a></span> 、 <span class="t-lc"><a href="cpp-atomic-atomic_store.html">std::atomic_store</a></span> 等）重载的函数进行。</p>
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<p>注意 shared_ptr 的控制块是线程安全的：多个线程能同时用可改操作访问不同的 <span class="t-lc"><a href="cpp-memory-shared_ptr.html">std::shared_ptr</a></span> 对象，如 operator= 或 reset ，即使这些实例是副本，并内部共享同一控制块。</p>
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<div class="t-li1"><span class="t-li">1)</span> 确定到 <code>p</code> 所指向共享指针的原子访问是否无锁。</div>
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<div class="t-li1"><span class="t-li">2)</span> 等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp">atomic_load_explicit<span class="br0">(</span>p, <a href="cpp-atomic-memory_order.html"><span class="kw2098">std::<span class="me2">memory_order_seq_cst</span></span></a><span class="br0">)</span></span></span> 。</div>
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<div class="t-li1"><span class="t-li">3)</span> 返回 <code>p</code> 所指向的共享指针。同非特化的 <span class="t-lc"><a href="cpp-atomic-atomic_load.html">std::atomic_load_explicit</a></span> ， <code>mo</code> 不能是 <span class="t-lc"><a href="cpp-atomic-memory_order.html">std::memory_order_release</a></span> 或 <span class="t-lc"><a href="cpp-atomic-memory_order.html">std::memory_order_acq_rel</a></span> 。</div>
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<div class="t-li1"><span class="t-li">4)</span> 等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp">atomic_store_explicit<span class="br0">(</span>p, r, memory_order_seq_cst<span class="br0">)</span></span></span> 。</div>
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<div class="t-li1"><span class="t-li">5)</span> 原子地存储共享指针 <code>r</code> 于 <code>p</code> 所指向的共享指针，等效地执行 <span class="t-c"><span class="mw-geshi cpp source-cpp">p<span class="sy2">-</span><span class="sy1">></span>swap<span class="br0">(</span>r<span class="br0">)</span></span></span> 。同非特化的 <span class="t-lc"><a href="cpp-atomic-atomic_store.html">std::atomic_store_explicit</a></span> 、 <code>mo</code> 不能是 <span class="t-lc"><a href="cpp-atomic-memory_order.html">std::memory_order_acquire</a></span> 或 <span class="t-lc"><a href="cpp-atomic-memory_order.html">std::memory_order_acq_rel</a></span> 。</div>
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<div class="t-li1"><span class="t-li">6)</span> 等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp">atomic_exchange_explicit<span class="br0">(</span>p, r, memory_order_seq_cst<span class="br0">)</span></span></span> 。</div>
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<div class="t-li1"><span class="t-li">7)</span> 原子地存储共享指针 <code>r</code> 于 <code>p</code> 所指向的共享指针，并返回 <code>p</code> 先前指向的值。等效地执行 <span class="t-c"><span class="mw-geshi cpp source-cpp">p<span class="sy2">-</span><span class="sy1">></span>swap<span class="br0">(</span>r<span class="br0">)</span></span></span> 并返回交换后 <code>r</code> 的副本。</div>
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<div class="t-li1"><span class="t-li">8)</span> 等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp">atomic_compare_exchange_weak_explicit<span class="br0">(</span>p, expected, desired, <a href="cpp-atomic-memory_order.html"><span class="kw2098">std::<span class="me2">memory_order_seq_cst</span></span></a>, <a href="cpp-atomic-memory_order.html"><span class="kw2098">std::<span class="me2">memory_order_seq_cst</span></span></a><span class="br0">)</span></span></span> 。</div>
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<div class="t-li1"><span class="t-li">9)</span> 等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp">atomic_compare_exchange_strong_explicit<span class="br0">(</span>p, expected, desired, <a href="cpp-atomic-memory_order.html"><span class="kw2098">std::<span class="me2">memory_order_seq_cst</span></span></a>, <a href="cpp-atomic-memory_order.html"><span class="kw2098">std::<span class="me2">memory_order_seq_cst</span></span></a><span class="br0">)</span></span></span> 。</div>
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<div class="t-li1"><span class="t-li">10)</span> 比较 <code>p</code> 所指向的共享指针和 <code>expected</code> 。若它们等价（存储同一指针值，并且共享同一对象的所有权或均为空），则用 <code>success</code> 所指定的内存定序制约赋值 <code>desired</code> 给 <code>*p</code> 并返回 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> 。若它们不等价，则用 <code>failure</code> 所指定的内存定序制约赋值 <code>*p</code> 给 <code>*expected</code> 并返回 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> 。</div>
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<div class="t-li1"><span class="t-li">11)</span> 同 10) ，但可能虚假地失败。</div>
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<p>若 <code>p</code> 为空指针，则这些函数都会引发未定义行为。</p>
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<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
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<table class="t-par-begin">
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<tr class="t-par">
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<td>p, expected</td>
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<td>-</td>
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<td>指向 <span class="t-lc"><a href="cpp-memory-shared_ptr.html">std::shared_ptr</a></span> 的指针</td>
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</tr>
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<tr class="t-par">
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<td>r, desired</td>
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<td>-</td>
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<td>一个 <span class="t-lc"><a href="cpp-memory-shared_ptr.html">std::shared_ptr</a></span></td>
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</tr>
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<tr class="t-par">
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<td>mo, success, failure</td>
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<td>-</td>
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<td><span class="t-lc"><a href="cpp-atomic-memory_order.html">std::memory_order</a></span> 类型的内存定序选择器</td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">异常</span></h3>
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<p>这些函数不抛异常。</p>
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<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">返回值</span></h3>
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<div class="t-li1"><span class="t-li">1)</span> 若原子访问使用无锁指令则为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span></div>
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<div class="t-li1"><span class="t-li">2,3)</span> 被指向的共享指针的副本。</div>
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<div class="t-li1"><span class="t-li">4,5)</span> （无）</div>
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<div class="t-li1"><span class="t-li">6,7)</span> 先前被指向共享指针的副本</div>
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<div class="t-li1"><span class="t-li">8,9,10,11)</span> 若共享指针等价并进行交换则为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> ，否则为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> 。</div>
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<h3><span class="mw-headline" id=".E6.B3.A8.E6.84.8F">注意</span></h3>
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<p>这些函数典型地以互斥实现，互斥存储于全局哈希表中，其中以指针值为关键。</p>
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<p>为避免数据竞争，一旦把共享指针传递给这些函数，就不能非原子地使用它。特别是，若你没有首先把这种 shared_ptr 加载到另一 shared_ptr 对象中，再通过第二对象解引用，就不能解引用它。</p>
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<p><a href="cpp-experimental-concurrency.html">并发 TS</a> 提供原子智能指针类 <code>atomic_shared_ptr</code> 和 <code>atomic_weak_ptr</code> ，以替换这些函数的使用。</p>
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<table class="t-rev-begin">
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<tr class="t-rev t-since-cxx20">
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<td>
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<p>这些函数被弃用，取代者是 <span class="t-lc"><a href="cpp-atomic-atomic.html">std::atomic</a></span> 模板的特化： <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span><a href="cpp-memory-shared_ptr.html"><span class="kw734">std::<span class="me2">shared_ptr</span></span></a><span class="sy1">></span></span></span> 和 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-atomic-atomic.html"><span class="kw2066">std::<span class="me2">atomic</span></span></a><span class="sy1"><</span><a href="cpp-memory-weak_ptr.html"><span class="kw741">std::<span class="me2">weak_ptr</span></span></a><span class="sy1">></span></span></span> 。</p>
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</td>
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<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
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</tr>
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</table>
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|
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
|
|
<table class="metadata plainlinks ambox mbox-small-left ambox-notice" style="">
|
|
<tr>
|
|
<td class="mbox-empty-cell"></td>
|
|
<td class="mbox-text" style="">本节未完成<br />
|
|
原因：暂无示例</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E7.BC.BA.E9.99.B7.E6.8A.A5.E5.91.8A">缺陷报告</span></h3>
|
|
<p>下列更改行为的缺陷报告追溯地应用于以前出版的 C++ 标准。</p>
|
|
<table class="dsctable" style="font-size:0.8em">
|
|
<tr>
|
|
<th>DR</th>
|
|
<th>应用于</th>
|
|
<th>出版时的行为</th>
|
|
<th>正确行为</th>
|
|
</tr>
|
|
<tr>
|
|
<td><a rel="nofollow" class="external text" href="https://cplusplus.github.io/LWG/issue2980">LWG 2980</a></td>
|
|
<td>C++11</td>
|
|
<td>空的 <code>shared_ptr</code> 决不等价</td>
|
|
<td>若它们存储同一指针值则等价</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-atomic-atomic_is_lock_free.html"><span class="t-lines"><span>atomic_is_lock_free</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>检查对该原子类型的操作是否是无锁的<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-atomic-atomic_store.html"><span class="t-lines"><span>atomic_store</span><span>atomic_store_explicit</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>原子地以非原子实参替换原子对象的值<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-atomic-atomic_load.html"><span class="t-lines"><span>atomic_load</span><span>atomic_load_explicit</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>原子地获得存储于原子对象的值<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-atomic-atomic_exchange.html"><span class="t-lines"><span>atomic_exchange</span><span>atomic_exchange_explicit</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>原子地以非原子实参的值替换原子对象的值，并返回该原子对象的旧值<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-atomic-atomic_compare_exchange.html"><span class="t-lines"><span>atomic_compare_exchange_weak</span><span>atomic_compare_exchange_weak_explicit</span><span>atomic_compare_exchange_strong</span><span>atomic_compare_exchange_strong_explicit</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>原子地比较原子对象和非原子实参的值，若相等则进行 atomic_exchange，若不相等则进行 atomic_load<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
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</body>
|
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</html>
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