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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>rewind</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-io.html">io</a>&lrm; | <a href="cpp-io-c.html">c</a></span></div>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-cstdio.html">&lt;cstdio&gt;</a></code></div>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw4">void</span> rewind<span class="br0">(</span> <a href="cpp-io-c.html"><span class="kw1876">std::<span class="me2">FILE</span></span></a><span class="sy2">*</span> stream <span class="br0">)</span><span class="sy4">;</span></span></div>
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<p>&#31227;&#21160;&#25991;&#20214;&#20301;&#32622;&#25351;&#31034;&#22120;&#21040;&#32473;&#23450;&#25991;&#20214;&#27969;&#30340;&#36215;&#22987;&#12290;</p>
<p>&#20989;&#25968;&#31561;&#20215;&#20110; <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-io-c-fseek.html"><span class="kw1867">std::<span class="me2">fseek</span></span></a><span class="br0">(</span>stream, <span class="nu0">0</span>, <a href="cpp-io-c.html"><span class="kw1888">SEEK_SET</span></a><span class="br0">)</span><span class="sy4">;</span></span></span> &#65292;&#38500;&#20102;&#23427;&#28165;&#38500;&#25991;&#20214;&#23614;&#21644;&#38169;&#35823;&#25351;&#31034;&#22120;&#12290;</p>
<p>&#27492;&#20989;&#25968;&#20002;&#24323;&#20219;&#20309;&#26469;&#33258;&#20808;&#21069;&#23545; <span class="t-lc">ungetc</span> &#35843;&#29992;&#30340;&#25928;&#26524;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>&#35201;&#20462;&#25913;&#30340;&#25991;&#20214;&#27969;</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>&#65288;&#26080;&#65289;</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;cstdio&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
<a href="cpp-io-c.html"><span class="kw1876">std::<span class="me2">FILE</span></span></a> <span class="sy2">*</span>f<span class="sy4">;</span>
<span class="kw4">char</span> ch<span class="sy4">;</span>
<span class="kw4">char</span> str<span class="br0">[</span><span class="nu0">20</span><span class="br0">]</span><span class="sy4">;</span>
f <span class="sy1">=</span> <a href="cpp-io-c-fopen.html"><span class="kw1813">std::<span class="me2">fopen</span></span></a><span class="br0">(</span><span class="st0">&quot;file.txt&quot;</span>, <span class="st0">&quot;w&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">for</span> <span class="br0">(</span>ch <span class="sy1">=</span> <span class="st0">&#39;0&#39;</span><span class="sy4">;</span> ch <span class="sy1">&lt;=</span> <span class="st0">&#39;9&#39;</span><span class="sy4">;</span> ch<span class="sy2">++</span><span class="br0">)</span> <span class="br0">{</span>
<a href="cpp-io-c-fputc.html"><span class="kw1824">std::<span class="me2">fputc</span></span></a><span class="br0">(</span>ch, f<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<a href="cpp-io-c-fclose.html"><span class="kw1816">std::<span class="me2">fclose</span></span></a><span class="br0">(</span>f<span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-c.html"><span class="kw1876">std::<span class="me2">FILE</span></span></a><span class="sy2">*</span> f2 <span class="sy1">=</span> <a href="cpp-io-c-fopen.html"><span class="kw1813">std::<span class="me2">fopen</span></span></a><span class="br0">(</span><span class="st0">&quot;file.txt&quot;</span>, <span class="st0">&quot;r&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">unsigned</span> <span class="kw4">int</span> size <span class="sy1">=</span> <a href="cpp-io-c-fread.html"><span class="kw1819">std::<span class="me2">fread</span></span></a><span class="br0">(</span>str, <span class="nu0">1</span>, <span class="nu0">10</span>, f2<span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-c-puts.html"><span class="kw1830">std::<span class="me2">puts</span></span></a><span class="br0">(</span>str<span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-c-fprintf.html"><span class="kw1845">std::<span class="me2">printf</span></span></a><span class="br0">(</span><span class="st0">&quot;<span class="es1">\n</span>%u<span class="es1">\n</span>&quot;</span>,size<span class="br0">)</span><span class="sy4">;</span>
std<span class="sy4">::</span><span class="me2">rewind</span><span class="br0">(</span>f2<span class="br0">)</span><span class="sy4">;</span>
<span class="kw4">unsigned</span> <span class="kw4">int</span> size2 <span class="sy1">=</span> <a href="cpp-io-c-fread.html"><span class="kw1819">std::<span class="me2">fread</span></span></a><span class="br0">(</span>str, <span class="nu0">1</span>, <span class="nu0">10</span>, f2<span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-c-puts.html"><span class="kw1830">std::<span class="me2">puts</span></span></a><span class="br0">(</span>str<span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-c-fprintf.html"><span class="kw1845">std::<span class="me2">printf</span></span></a><span class="br0">(</span><span class="st0">&quot;<span class="es1">\n</span>%u&quot;</span>,size2<span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-c-fclose.html"><span class="kw1816">std::<span class="me2">fclose</span></span></a><span class="br0">(</span>f2<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span></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-io-c-fseek.html"><span class="t-lines"><span>fseek</span></span></a></div>
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<td>&#31227;&#21160;&#25991;&#20214;&#20301;&#32622;&#25351;&#31034;&#22120;&#21040;&#25991;&#20214;&#20013;&#30340;&#25351;&#23450;&#20301;&#32622;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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