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<h1 id="firstHeading" class="firstHeading">fsetpos</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="c.html">c</a>&lrm; | <a href="c-io.html">io</a></span></div>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code>&lt;stdio.h&gt;</code></div>
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<div><span class="mw-geshi c source-c"><span class="kw4">int</span> fsetpos<span class="br0">(</span> <a href="c-io.html"><span class="kw883">FILE</span></a> <span class="sy2">*</span>stream, <span class="kw4">const</span> <a href="c-io.html"><span class="kw884">fpos_t</span></a> <span class="sy2">*</span>pos <span class="br0">)</span><span class="sy4">;</span></span></div>
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<p>&#25353;&#29031; <code>pos</code> &#25152;&#25351;&#21521;&#30340;&#20540;&#65292;&#35774;&#32622;&#25991;&#20214;&#27969; <code>stream</code> &#30340;&#25991;&#20214;&#20301;&#32622;&#25351;&#31034;&#22120;&#21644;&#22810;&#23383;&#33410;&#20998;&#26512;&#29366;&#24577;&#65288;&#33509;&#23384;&#22312;&#65289;&#12290;</p>
<p>&#38500;&#20102;&#24314;&#31435;&#26032;&#30340;&#20998;&#26512;&#29366;&#24577;&#21644;&#20301;&#32622;&#65292;&#35843;&#29992;&#27492;&#20989;&#25968;&#36824;&#20250;&#25764;&#38144; <span class="t-lc"><a href="c-io-ungetc.html">ungetc</a></span> &#30340;&#25928;&#26524;&#65292;&#24182;&#33509;&#35774;&#32622;&#20102;&#25991;&#20214;&#23614;&#29366;&#24577;&#21017;&#28165;&#38500;&#20043;&#12290;</p>
<p>&#33509;&#35835;&#25110;&#20889;&#20986;&#29616;&#38169;&#35823;&#65292;&#21017;&#35774;&#32622;&#27969;&#30340;&#38169;&#35823;&#25351;&#31034;&#22120;&#65288; <span class="t-lc"><a href="c-io-ferror.html">ferror</a></span> &#65289;&#12290;</p>
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">&#21442;&#25968;</span></h3>
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<td>stream</td>
<td>-</td>
<td>&#35201;&#20462;&#25913;&#30340;&#25991;&#20214;&#27969;</td>
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<td>pos</td>
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<td>&#25351;&#21521; <span class="t-c"><span class="mw-geshi c source-c"><a href="c-io.html"><span class="kw884">fpos_t</span></a></span></span> &#23545;&#35937;&#30340;&#25351;&#38024;&#65292;&#29992;&#20316;&#25991;&#20214;&#20301;&#32622;&#25351;&#31034;&#22120;&#30340;&#26032;&#20540;</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>&#25104;&#21151;&#26102;&#20026; <span class="t-c"><span class="mw-geshi c source-c">&#8203;<span class="nu0">0</span>&#8203;</span></span> &#65292;&#21542;&#21017;&#20026;&#38750;&#38646;&#20540;&#12290;</p>
<h3><span class="mw-headline" id=".E6.B3.A8.E6.84.8F">&#27880;&#24847;</span></h3>
<p>&#22312;&#23547;&#20301;&#21040;&#23485;&#27969;&#30340;&#38750;&#32467;&#23614;&#20301;&#32622;&#21518;&#65292;&#19979;&#20010;&#23545;&#20219;&#20309;&#36755;&#20986;&#20989;&#25968;&#30340;&#35843;&#29992;&#21487;&#33021;&#20351;&#21097;&#19979;&#30340;&#25991;&#20214;&#20869;&#23481;&#26410;&#23450;&#20041;&#65292;&#20363;&#22914;&#36890;&#36807;&#36755;&#20986;&#19981;&#21516;&#38271;&#24230;&#30340;&#22810;&#23383;&#33410;&#24207;&#21015;&#12290;</p>
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
<div class="t-example">
<p>fsetpos &#24102;&#38169;&#35823;&#26816;&#26597;</p>
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<pre class="de1"><span class="co2">#include &lt;stdio.h&gt;</span>
<span class="co2">#include &lt;stdlib.h&gt;</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="kw4">void</span><span class="br0">)</span>
<span class="br0">{</span>
<span class="coMULTI">/* &#20934;&#22791;&#19968;&#20010;&#28014;&#28857;&#20540;&#30340;&#25968;&#32452;&#12290; */</span>
<span class="co2">#define SIZE 5</span>
<span class="kw4">double</span> A<span class="br0">[</span>SIZE<span class="br0">]</span> <span class="sy1">=</span> <span class="br0">{</span><span class="nu0">1</span>.,<span class="nu0">2</span>.,<span class="nu0">3</span>.,<span class="nu0">4</span>.,<span class="nu0">5</span>.<span class="br0">}</span><span class="sy4">;</span>
<span class="coMULTI">/* &#20889;&#25968;&#32452;&#21040;&#25991;&#20214;&#12290; */</span>
<a href="c-io.html"><span class="kw883">FILE</span></a> <span class="sy2">*</span> fp <span class="sy1">=</span> <a href="c-io-fopen.html"><span class="kw819">fopen</span></a><span class="br0">(</span><span class="st0">&quot;test.bin&quot;</span>, <span class="st0">&quot;wb&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fwrite.html"><span class="kw826">fwrite</span></a><span class="br0">(</span>A,<span class="kw4">sizeof</span><span class="br0">(</span><span class="kw4">double</span><span class="br0">)</span>,SIZE,fp<span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fclose.html"><span class="kw822">fclose</span></a> <span class="br0">(</span>fp<span class="br0">)</span><span class="sy4">;</span>
<span class="coMULTI">/* &#35835;&#21462;&#28014;&#28857;&#20540;&#21040;&#25968;&#32452;B&#12290; */</span>
<span class="kw4">double</span> B<span class="br0">[</span>SIZE<span class="br0">]</span><span class="sy4">;</span>
fp <span class="sy1">=</span> <a href="c-io-fopen.html"><span class="kw819">fopen</span></a><span class="br0">(</span><span class="st0">&quot;test.bin&quot;</span>,<span class="st0">&quot;rb&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-io.html"><span class="kw884">fpos_t</span></a> pos<span class="sy4">;</span>
<span class="kw1">if</span> <span class="br0">(</span><a href="c-io-fgetpos.html"><span class="kw872">fgetpos</span></a><span class="br0">(</span>fp,<span class="sy3">&amp;</span>pos<span class="br0">)</span> <span class="sy3">!</span><span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="coMULTI">/* &#24403;&#21069;&#20301;&#32622;&#65306;&#25991;&#20214;&#36215;&#22987; */</span>
<span class="br0">{</span>
<a href="c-io-perror.html"><span class="kw878">perror</span></a><span class="br0">(</span><span class="st0">&quot;fgetpos()&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw852">fprintf</span></a><span class="br0">(</span><a href="c-io.html"><span class="kw887">stderr</span></a>,<span class="st0">&quot;fgetpos() failed in file %s at line # %d<span class="es1">\n</span>&quot;</span>, __FILE__,__LINE__<span class="sy2">-</span><span class="nu0">3</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-program-exit.html"><span class="kw488">exit</span></a><span class="br0">(</span><a href="c-program-EXIT_status.html"><span class="kw494">EXIT_FAILURE</span></a><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw4">int</span> ret_code <span class="sy1">=</span> <a href="c-io-fread.html"><span class="kw825">fread</span></a><span class="br0">(</span>B,<span class="kw4">sizeof</span><span class="br0">(</span><span class="kw4">double</span><span class="br0">)</span>,<span class="nu0">1</span>,fp<span class="br0">)</span><span class="sy4">;</span> <span class="coMULTI">/* &#35835;&#21462;&#19968;&#20010;&#28014;&#28857;&#20540; */</span>
<span class="coMULTI">/* &#24403;&#21069;&#20301;&#32622;&#65306;&#22312;&#35835;&#19968;&#20010;&#28014;&#28857;&#20540;&#21518; */</span>
<a href="c-io-fprintf.html"><span class="kw851">printf</span></a><span class="br0">(</span><span class="st0">&quot;%.1f<span class="es1">\n</span>&quot;</span>, B<span class="br0">[</span><span class="nu0">0</span><span class="br0">]</span><span class="br0">)</span><span class="sy4">;</span> <span class="coMULTI">/* &#25171;&#21360;&#19968;&#20010;&#28014;&#28857;&#20540; */</span>
<span class="kw1">if</span> <span class="br0">(</span>fsetpos<span class="br0">(</span>fp,<span class="sy3">&amp;</span>pos<span class="br0">)</span> <span class="sy3">!</span><span class="sy1">=</span> <span class="nu0">0</span><span class="br0">)</span> <span class="coMULTI">/* &#37325;&#35774;&#24403;&#21069;&#20301;&#32622;&#20026;&#25991;&#20214;&#36215;&#22987; */</span>
<span class="br0">{</span>
<span class="kw1">if</span> <span class="br0">(</span><a href="c-io-ferror.html"><span class="kw877">ferror</span></a><span class="br0">(</span>fp<span class="br0">)</span><span class="br0">)</span>
<span class="br0">{</span>
<a href="c-io-perror.html"><span class="kw878">perror</span></a><span class="br0">(</span><span class="st0">&quot;fsetpos()&quot;</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-io-fprintf.html"><span class="kw852">fprintf</span></a><span class="br0">(</span><a href="c-io.html"><span class="kw887">stderr</span></a>,<span class="st0">&quot;fsetpos() failed in file %s at line # %d<span class="es1">\n</span>&quot;</span>, __FILE__,__LINE__<span class="sy2">-</span><span class="nu0">5</span><span class="br0">)</span><span class="sy4">;</span>
<a href="c-program-exit.html"><span class="kw488">exit</span></a><span class="br0">(</span><a href="c-program-EXIT_status.html"><span class="kw494">EXIT_FAILURE</span></a><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="br0">}</span>
ret_code <span class="sy1">=</span> <a href="c-io-fread.html"><span class="kw825">fread</span></a><span class="br0">(</span>B,<span class="kw4">sizeof</span><span class="br0">(</span><span class="kw4">double</span><span class="br0">)</span>,<span class="nu0">1</span>,fp<span class="br0">)</span><span class="sy4">;</span> <span class="coMULTI">/* &#37325;&#35835;&#39318;&#20010;&#28014;&#28857;&#20540; */</span>
<a href="c-io-fprintf.html"><span class="kw851">printf</span></a><span class="br0">(</span><span class="st0">&quot;%.1f<span class="es1">\n</span>&quot;</span>, B<span class="br0">[</span><span class="nu0">0</span><span class="br0">]</span><span class="br0">)</span><span class="sy4">;</span> <span class="coMULTI">/* &#25171;&#21360;&#19968;&#20010;&#28014;&#28857;&#20540; */</span>
<a href="c-io-fclose.html"><span class="kw822">fclose</span></a><span class="br0">(</span>fp<span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">return</span> <a href="c-program-EXIT_status.html"><span class="kw493">EXIT_SUCCESS</span></a><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
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<p>&#36755;&#20986;&#65306;</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="text source-text">
<pre class="de1">1.0
1.0</pre></div>
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<h3><span class="mw-headline" id=".E5.BC.95.E7.94.A8">&#24341;&#29992;</span></h3>
<div class="t-ref-std-11">
<ul>
<li>C11 &#26631;&#20934;&#65288;ISO/IEC 9899:2011&#65289;&#65306;</li>
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<dd>
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<li>7.21.9.3 The fsetpos function (p: 337)</li>
</ul>
</dd>
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<div class="t-ref-std-c99">
<ul>
<li>C99 &#26631;&#20934;&#65288;ISO/IEC 9899:1999&#65289;&#65306;</li>
</ul>
<dl>
<dd>
<ul>
<li>7.19.9.3 The fsetpos function (p: 303)</li>
</ul>
</dd>
</dl>
<div class="t-ref-std-c89">
<ul>
<li>C89/C90 &#26631;&#20934;&#65288;ISO/IEC 9899:1990&#65289;&#65306;</li>
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<dd>
<ul>
<li>4.9.9.3 The fsetpos function</li>
</ul>
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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="c-io-fgetpos.html"><span class="t-lines"><span>fgetpos</span></span></a></div>
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<td>&#33719;&#21462;&#25991;&#20214;&#20301;&#32622;&#25351;&#31034;&#22120;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<div class="t-dsc-member-div">
<div><a href="c-io-ftell.html"><span class="t-lines"><span>ftell</span></span></a></div>
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<td>&#36820;&#22238;&#24403;&#21069;&#30340;&#25991;&#20214;&#20301;&#32622;&#25351;&#31034;&#20540;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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<div><a href="c-io-fseek.html"><span class="t-lines"><span>fseek</span></span></a></div>
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<td>&#23558;&#25991;&#20214;&#20301;&#32622;&#25351;&#31034;&#31526;&#31227;&#21160;&#21040;&#25991;&#20214;&#20013;&#30340;&#25351;&#23450;&#20301;&#32622;<br />
<span class="t-mark">(&#20989;&#25968;)</span></td>
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