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<a name="fgetpos"></a>
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<div class="header">
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<p>
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Next: <a href="fgets.html#fgets" accesskey="n" rel="next">fgets</a>, Previous: <a href="fgetc.html#fgetc" accesskey="p" rel="prev">fgetc</a>, Up: <a href="Stdio.html#Stdio" accesskey="u" rel="up">Stdio</a> [<a href="Document-Index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Document-Index.html#Document-Index" title="Index" rel="index">Index</a>]</p>
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<hr>
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<a name="fgetpos_002d_002d_002drecord-position-in-a-stream-or-file"></a>
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<h3 class="section">4.11 <code>fgetpos</code>—record position in a stream or file</h3>
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<a name="index-fgetpos"></a>
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<a name="index-_005ffgetpos_005fr"></a>
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<p><strong>Synopsis</strong>
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</p><div class="example">
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<pre class="example">#include <stdio.h>
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int fgetpos(FILE *restrict <var>fp</var>, fpos_t *restrict <var>pos</var>);
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int _fgetpos_r(struct _reent *<var>ptr</var>, FILE *restrict <var>fp</var>, fpos_t *restrict <var>pos</var>);
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</pre></div>
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<p><strong>Description</strong><br>
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Objects of type <code>FILE</code> can have a “position” that records how much
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of the file your program has already read. Many of the <code>stdio</code> functions
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depend on this position, and many change it as a side effect.
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</p>
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<p>You can use <code>fgetpos</code> to report on the current position for a file
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identified by <var>fp</var>; <code>fgetpos</code> will write a value
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representing that position at <code>*<var>pos</var></code>. Later, you can
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use this value with <code>fsetpos</code> to return the file to this
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position.
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</p>
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<p>In the current implementation, <code>fgetpos</code> simply uses a character
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count to represent the file position; this is the same number that
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would be returned by <code>ftell</code>.
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</p>
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<br>
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<p><strong>Returns</strong><br>
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<code>fgetpos</code> returns <code>0</code> when successful. If <code>fgetpos</code> fails, the
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result is <code>1</code>. Failure occurs on streams that do not support
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positioning; the global <code>errno</code> indicates this condition with the
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value <code>ESPIPE</code>.
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</p>
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<br>
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<p><strong>Portability</strong><br>
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<code>fgetpos</code> is required by the ANSI C standard, but the meaning of the
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value it records is not specified beyond requiring that it be
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acceptable as an argument to <code>fsetpos</code>. In particular, other
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conforming C implementations may return a different result from
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<code>ftell</code> than what <code>fgetpos</code> writes at <code>*<var>pos</var></code>.
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</p>
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<p>No supporting OS subroutines are required.
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</p>
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