97 lines
9.2 KiB
HTML
97 lines
9.2 KiB
HTML
<!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::shared_timed_mutex::try_lock_shared_until</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_shared_timed_mutex_try_lock_shared_until skin-cppreference2 action-view 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::shared_timed_mutex::</span>try_lock_shared_until</h1>
|
|
<div id="bodyContent">
|
|
<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-thread.html">thread</a>‎ | <a href="cpp-thread-shared_timed_mutex.html">shared timed mutex</a></span></div>
|
|
<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
|
|
<table class="t-dcl-begin">
|
|
<tbody>
|
|
<tr class="t-dcl t-since-cxx14">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> Clock, <span class="kw1">class</span> Duration <span class="sy1">></span><br />
|
|
<span class="kw4">bool</span> try_lock_shared_until<span class="br0">(</span> <span class="kw4">const</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"><</span>Clock,Duration<span class="sy1">></span><span class="sy3">&</span> timeout_time <span class="br0">)</span><span class="sy4">;</span></span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx14">(C++14 起)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl-sep">
|
|
<td></td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>尝试以共享模式锁定互斥。阻塞直至抵达 <code>timeout_time</code> 或得到互斥，之先到来者。成功获得互斥时返回 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> ，否则返回 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> 。</p>
|
|
<p>若已经过 <code>timeout_time</code> ，则此函数表现同 <span class="t-lc"><a href="cpp-thread-shared_timed_mutex-try_lock_shared.html">try_lock_shared()</a></span> 。</p>
|
|
<p><code>Clock</code> 必须符合<a href="cpp-named_req-Clock.html"><span style="font-style:italic">时钟</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(Clock)</span></a> 要求。<span class="t-rev-inl t-since-cxx20"><span>若 <span class="t-c"><span class="mw-geshi cpp source-cpp">std<span class="sy4">::</span><span class="me2">chrono</span><span class="sy4">::</span><span class="me2">is_clock_v</span><span class="sy1"><</span>Clock<span class="sy1">></span></span></span> 为 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> 则程序为非良构。</span> <span><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></span></span></p>
|
|
<p>标准推荐使用绑定到 <code>timeout_time</code> 的时钟，该情况下可以计入时钟的调整。从而在调用时刻，阻塞的时长可以，但也可以不，小于或大于 <span class="t-c"><span class="mw-geshi cpp source-cpp">timeout_time <span class="sy2">-</span> Clock<span class="sy4">::</span><span class="me2">now</span><span class="br0">(</span><span class="br0">)</span></span></span> 。这取决于调整的方向以及实现是否尊重它。函数亦可能由于调度或资源纠纷延迟，而阻塞长于到抵达 <code>timeout_time</code> 之后。</p>
|
|
<p>同 <span class="t-lc"><a href="cpp-thread-shared_timed_mutex-try_lock_shared.html">try_lock_shared()</a></span> ，允许此函数虚假地失败而返回 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">false</span></span></span> ，即使在 <code>timeout_time</code> 前某点互斥不为任何其他线程所锁定。</p>
|
|
<p>若此操作返回 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> ，则同一互斥上先前的 <span class="t-lc"><a href="cpp-thread-shared_timed_mutex-unlock.html">unlock()</a></span> 操作<i>同步于</i>（定义于 <span class="t-lc"><a href="cpp-atomic-memory_order.html">std::memory_order</a></span> ）它。</p>
|
|
<p>若已以任何模式（共享或排他性）占有 <code>mutex</code> 的线程调用 <code>try_lock_shared_until</code> ，则行为未定义。</p>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
|
|
<table class="t-par-begin">
|
|
<tr class="t-par">
|
|
<td>timeout_time</td>
|
|
<td>-</td>
|
|
<td>要阻塞到的最大时间点</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">返回值</span></h3>
|
|
<p>若成功获得锁则为 <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> 。</p>
|
|
<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">异常</span></h3>
|
|
<p>任何时钟、时间点或时长在执行中抛出的异常（标准库提供的时钟、时间点及时长决不抛出）</p>
|
|
<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=".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-thread-shared_timed_mutex-try_lock_until.html"><span class="t-lines"><span>try_lock_until</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>尝试锁定互斥，若直至抵达指定时间点互斥不可用则返回<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-thread-shared_timed_mutex-try_lock_shared.html"><span class="t-lines"><span>try_lock_shared</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>尝试为共享所有权锁定互斥，若互斥不可用则返回<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-thread-shared_timed_mutex-try_lock_shared_for.html"><span class="t-lines"><span>try_lock_shared_for</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>尝试为共享所有权锁定互斥，若互斥在指定的时限时期中不可用则返回<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|