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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>strncpy</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-string.html">string</a>&lrm; | <a href="cpp-string-byte.html">byte</a></span></div>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-cstring.html">&lt;cstring&gt;</a></code></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">char</span> <span class="sy2">*</span>strncpy<span class="br0">(</span> <span class="kw4">char</span> <span class="sy2">*</span>dest, <span class="kw4">const</span> <span class="kw4">char</span> <span class="sy2">*</span>src, <a href="cpp-types-size_t.html"><span class="kw100">std::<span class="me2">size_t</span></span></a> count <span class="br0">)</span><span class="sy4">;</span></span></div>
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<p>&#22797;&#21046; <code>src</code> &#25152;&#25351;&#21521;&#30340;&#23383;&#33410;&#23383;&#31526;&#20018;&#30340;&#33267;&#22810; <code>count</code> &#20010;&#23383;&#31526;&#65288;&#21253;&#21547;&#32456;&#27490;&#31354;&#23383;&#31526;&#65289;&#21040; <code>dest</code> &#25152;&#25351;&#21521;&#30340;&#23383;&#31526;&#25968;&#32452;&#12290;</p>
<p>&#33509;&#22312;&#22797;&#21046;&#25972;&#20010;&#23383;&#31526;&#20018; <code>src</code> &#21069;&#25269;&#36798; <code>count</code> &#65292;&#21017;&#20135;&#29983;&#30340;&#23383;&#31526;&#25968;&#32452;&#19981;&#26159;&#31354;&#32456;&#27490;&#30340;&#12290;</p>
<p>&#33509;&#22312;&#22797;&#21046;&#26469;&#33258; <code>src</code> &#30340;&#32456;&#27490;&#31354;&#23383;&#31526;&#21518;&#26410;&#25269;&#36798; <code>count</code> &#65292;&#21017;&#20889;&#20837;&#39069;&#22806;&#30340;&#31354;&#23383;&#31526;&#21040; <code>dest</code> &#65292;&#30452;&#33267;&#20889;&#20837;&#24635;&#20849; <code>count</code> &#20010;&#23383;&#31526;&#12290;</p>
<p>&#33509;&#23383;&#31526;&#20018;&#37325;&#21472;&#65292;&#21017;&#34892;&#20026;&#26410;&#23450;&#20041;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>dest</td>
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<td>&#25351;&#21521;&#35201;&#22797;&#21046;&#21040;&#30340;&#23383;&#31526;&#25968;&#32452;&#30340;&#25351;&#38024;</td>
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<td>src</td>
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<td>&#25351;&#21521;&#20316;&#20026;&#22797;&#21046;&#26469;&#28304;&#30340;&#23383;&#33410;&#23383;&#31526;&#20018;&#30340;&#25351;&#38024;</td>
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<td>count</td>
<td>-</td>
<td>&#35201;&#22797;&#21046;&#30340;&#26368;&#22823;&#23383;&#31526;&#25968;</td>
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<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">&#36820;&#22238;&#20540;</span></h3>
<p><code>dest</code></p>
<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;iostream&gt;</span>
<span class="co2">#include &lt;cstring&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<span class="kw4">const</span> <span class="kw4">char</span><span class="sy2">*</span> src <span class="sy1">=</span> <span class="st0">&quot;hi&quot;</span><span class="sy4">;</span>
<span class="kw4">char</span> dest<span class="br0">[</span><span class="nu0">6</span><span class="br0">]</span> <span class="sy1">=</span> <span class="br0">{</span><span class="st0">&#39;a&#39;</span>, <span class="st0">&#39;b&#39;</span>, <span class="st0">&#39;c&#39;</span>, <span class="st0">&#39;d&#39;</span>, <span class="st0">&#39;e&#39;</span>, <span class="st0">&#39;f&#39;</span><span class="br0">}</span><span class="sy4">;</span>
std<span class="sy4">::</span><span class="me2">strncpy</span><span class="br0">(</span>dest, src, <span class="nu0">5</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;The contents of dest are: &quot;</span><span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span><span class="kw4">char</span> c <span class="sy4">:</span> dest<span class="br0">)</span> <span class="br0">{</span>
<span class="kw1">if</span> <span class="br0">(</span>c<span class="br0">)</span> <span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> c <span class="sy1">&lt;&lt;</span> <span class="st0">&#39; &#39;</span><span class="sy4">;</span>
<span class="br0">}</span> <span class="kw1">else</span> <span class="br0">{</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">&quot;<span class="es1">\\</span>0&quot;</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39; &#39;</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="br0">}</span>
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <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>&#36755;&#20986;&#65306;</p>
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<pre class="de1">The contents of dest are: h i \0 \0 \0 f</pre></div>
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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-string-byte-strcpy.html"><span class="t-lines"><span>strcpy</span></span></a></div>
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<td>&#22797;&#21046;&#19968;&#20010;&#23383;&#31526;&#20018;&#32473;&#21478;&#19968;&#20010;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<div><a href="cpp-string-byte-memcpy.html"><span class="t-lines"><span>memcpy</span></span></a></div>
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<td>&#22797;&#21046;&#19968;&#20010;&#32531;&#20914;&#21306;&#21040;&#21478;&#19968;&#20010;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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