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<title>&#26631;&#20934;&#24211;&#22836;&#25991;&#20214; &lt;cfenv&gt;</title>
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">&#26631;&#20934;&#24211;&#22836;&#25991;&#20214;</span> &lt;cfenv&gt;</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-header.html">header</a></span></div>
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<p>&#27492;&#22836;&#25991;&#20214;&#21407;&#20316;&#20026; <code><b>&lt;fenv.h&gt;</b></code> &#23384;&#22312;&#20110; C &#26631;&#20934;&#24211;&#12290;</p>
<p>&#27492;&#22836;&#25991;&#20214;&#26159;<a href="cpp-numeric-fenv.html">&#28014;&#28857;&#29615;&#22659;</a>&#24211;&#30340;&#19968;&#37096;&#20998;&#12290;</p>
<h3><span class="mw-headline" id=".E7.B1.BB.E5.9E.8B">&#31867;&#22411;</span></h3>
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp">fenv_t</span></span></td>
<td>&#34920;&#31034;&#25972;&#20010;&#28014;&#28857;&#29615;&#22659;&#30340;&#31867;&#22411;</td>
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<td><span class="t-c"><span class="mw-geshi cpp source-cpp">fexcept_t</span></span></td>
<td>&#27719;&#38598;&#22320;&#34920;&#31034;&#25152;&#26377;&#28014;&#28857;&#29366;&#24577;&#26631;&#24535;&#30340;&#31867;&#22411;</td>
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</table>
<h3><span class="mw-headline" id=".E5.87.BD.E6.95.B0">&#20989;&#25968;</span></h3>
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<div><a href="cpp-numeric-fenv-feclearexcept.html"><span class="t-lines"><span>feclearexcept</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>&#28165;&#38500;&#25351;&#23450;&#30340;&#28014;&#28857;&#29366;&#24577;&#26631;&#24535;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<td>
<div class="t-dsc-member-div">
<div><a href="cpp-numeric-fenv-fetestexcept.html"><span class="t-lines"><span>fetestexcept</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>
<td>&#30830;&#23450;&#35774;&#32622;&#20102;&#21738;&#20010;&#25351;&#23450;&#30340;&#28014;&#28857;&#29366;&#24577;&#26631;&#24535;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<td>
<div class="t-dsc-member-div">
<div><a href="cpp-numeric-fenv-feraiseexcept.html"><span class="t-lines"><span>feraiseexcept</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>&#24341;&#21457;&#25351;&#23450;&#30340;&#28014;&#28857;&#24322;&#24120;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-numeric-fenv-feexceptflag.html"><span class="t-lines"><span>fegetexceptflag</span><span>fesetexceptflag</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>&#20174;&#28014;&#28857;&#29615;&#22659;&#65288;&#25110;&#21521;&#20854;&#20013;&#65289;&#22797;&#21046;&#25351;&#23450;&#30340;&#28014;&#28857;&#29366;&#24577;&#26631;&#24535;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<div><a href="cpp-numeric-fenv-feround.html"><span class="t-lines"><span>fegetround</span><span>fesetround</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>&#33719;&#21462;&#25110;&#35774;&#32622;&#33293;&#20837;&#26041;&#21521;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<div><a href="cpp-numeric-fenv-feenv.html"><span class="t-lines"><span>fegetenv</span><span>fesetenv</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>
<td>&#20445;&#23384;&#25110;&#24674;&#22797;&#24403;&#21069;&#28014;&#28857;&#29615;&#22659;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-numeric-fenv-feholdexcept.html"><span class="t-lines"><span>feholdexcept</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>&#20445;&#23384;&#29615;&#22659;&#65292;&#28165;&#38500;&#25152;&#26377;&#29366;&#24577;&#26631;&#24535;&#65292;&#24182;&#24573;&#30053;&#25152;&#26377;&#23558;&#26469;&#30340;&#38169;&#35823;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<td>
<div class="t-dsc-member-div">
<div><a href="cpp-numeric-fenv-feupdateenv.html"><span class="t-lines"><span>feupdateenv</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>
<td>&#24674;&#22797;&#28014;&#28857;&#29615;&#22659;&#24182;&#24341;&#21457;&#20043;&#21069;&#24341;&#21457;&#30340;&#24322;&#24120;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<h3><span class="mw-headline" id=".E5.AE.8F">&#23439;</span></h3>
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<div><a href="cpp-numeric-fenv-FE_exceptions.html"><span class="t-lines"><span>FE_ALL_EXCEPT</span><span>FE_DIVBYZERO</span><span>FE_INEXACT</span><span>FE_INVALID</span><span>FE_OVERFLOW</span><span>FE_UNDERFLOW</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>&#28014;&#28857;&#24322;&#24120;<br />
<span class="t-mark">(&#23439;&#24120;&#37327;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-numeric-fenv-FE_round.html"><span class="t-lines"><span>FE_DOWNWARD</span><span>FE_TONEAREST</span><span>FE_TOWARDZERO</span><span>FE_UPWARD</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>&#28014;&#28857;&#33293;&#20837;&#26041;&#21521;<br />
<span class="t-mark">(&#23439;&#24120;&#37327;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="cpp-numeric-fenv-FE_DFL_ENV.html"><span class="t-lines"><span>FE_DFL_ENV</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>
<td>&#40664;&#35748;&#28014;&#28857;&#29615;&#22659;<br />
<span class="t-mark">(&#23439;&#24120;&#37327;)</span></td>
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<h3><span class="mw-headline" id=".E6.A6.82.E8.A6.81">&#27010;&#35201;</span></h3>
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<pre class="de1"><span class="kw1">namespace</span> std <span class="br0">{</span>
<span class="co1">// &#31867;&#22411;</span>
<span class="kw1">typedef</span> <span class="coMULTI">/*&#23545;&#35937;&#31867;&#22411;*/</span> fenv_t<span class="sy4">;</span>
<span class="kw1">typedef</span> <span class="coMULTI">/*&#25972;&#25968;&#31867;&#22411;*/</span> fexcept_t<span class="sy4">;</span>
<span class="co1">// &#20989;&#25968;</span>
<span class="kw4">int</span> feclearexcept<span class="br0">(</span><span class="kw4">int</span> except<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">int</span> fegetexceptflag<span class="br0">(</span>fexcept_t <span class="sy2">*</span>pflag, <span class="kw4">int</span> except<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">int</span> feraiseexcept<span class="br0">(</span><span class="kw4">int</span> except<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">int</span> fesetexceptflag<span class="br0">(</span><span class="kw4">const</span> fexcept_t <span class="sy2">*</span>pflag, <span class="kw4">int</span> except<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">int</span> fetestexcept<span class="br0">(</span><span class="kw4">int</span> except<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">int</span> fegetround<span class="br0">(</span><span class="kw4">void</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">int</span> fesetround<span class="br0">(</span><span class="kw4">int</span> mode<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">int</span> fegetenv<span class="br0">(</span>fenv_t <span class="sy2">*</span>penv<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">int</span> feholdexcept<span class="br0">(</span>fenv_t <span class="sy2">*</span>penv<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">int</span> fesetenv<span class="br0">(</span><span class="kw4">const</span> fenv_t <span class="sy2">*</span>penv<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">int</span> feupdateenv<span class="br0">(</span><span class="kw4">const</span> fenv_t <span class="sy2">*</span>penv<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
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