devdocs/c/io%2Frewind.html


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    <h1 id="firstHeading" class="firstHeading">rewind</h1>            <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code>&lt;stdio.h&gt;</code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl"> <td class="t-dcl-nopad"> <pre data-language="c">void rewind( FILE *stream );</pre>
</td> <td class="t-dcl-nopad"> </td> <td class="t-dcl-nopad"> </td> </tr>  </table> <p>Moves the file position indicator to the beginning of the given file stream.</p>
<p>The function is equivalent to <code><a href="http://en.cppreference.com/w/c/io/fseek"><span class="kw873">fseek</span></a><span class="br0">(</span>stream, <span class="nu0">0</span>, <a href="http://en.cppreference.com/w/c/io"><span class="kw895">SEEK_SET</span></a><span class="br0">)</span><span class="sy4">;</span></code>, except that end-of-file and error indicators are cleared.</p>
<p>The function drops any effects from previous calls to <code><a href="ungetc" title="c/io/ungetc">ungetc</a></code>.</p>
<h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> stream </td> <td> - </td> <td> file stream to modify </td>
</tr>
</table> <h3 id="Return_value"> Return value</h3> <p>(none)</p>
<h3 id="Example"> Example</h3> <div class="t-example">
<p>This example shows how to read a file twice</p>
<div class="c source-c"><pre data-language="c">#include &lt;stdio.h&gt;
 
char str[20];
 
int main(void)
{
    FILE *f;
    char ch;
 
    f = fopen("file.txt", "w");
    for (ch = '0'; ch &lt;= '9'; ch++) {
        fputc(ch, f);
    }
    fclose(f);
 
    f = fopen("file.txt", "r");
    fread(str, 1, 10, f);
    puts(str);
 
    rewind(f);
    fread(str, 1, 10, f);
    puts(str);
    fclose(f);
 
    return 0;
}</pre></div> <p>Output:</p>
<div class="text source-text"><pre data-language="c">0123456789
0123456789</pre></div> </div> <h3 id="References"> References</h3>  <ul>
<li> C11 standard (ISO/IEC 9899:2011): </li>
<ul><li> 7.21.9.5 The rewind function (p: 338) </li></ul>
<li> C99 standard (ISO/IEC 9899:1999): </li>
<ul><li> 7.19.9.5 The rewind function (p: 304) </li></ul>
<li> C89/C90 standard (ISO/IEC 9899:1990): </li>
<ul><li> 4.9.9.5 The rewind function </li></ul>
</ul>         <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="fseek" title="c/io/fseek"> <span class="t-lines"><span>fseek</span></span></a></div> </td> <td> moves the file position indicator to a specific location in a file <br> <span class="t-mark">(function)</span>  </td>
</tr> <tr class="t-dsc"> <td colspan="2"> <span><a href="https://en.cppreference.com/w/cpp/io/c/rewind" title="cpp/io/c/rewind">C++ documentation</a></span> for <code>rewind</code> </td>
</tr> </table>            <div class="_attribution">
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    &copy; cppreference.com<br>Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.<br>
    <a href="https://en.cppreference.com/w/c/io/rewind" class="_attribution-link">https://en.cppreference.com/w/c/io/rewind</a>
  </p>
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