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<title>Issue 6: File position not an offset unimplementable</title>
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<p><em>This page is a snapshot from the LWG issues list, see the <a href="lwg-active.html">Library Active Issues List</a> for more information and the meaning of <a href="lwg-active.html#NAD">NAD</a> status.</em></p>
<h3 id="6"><a href="lwg-closed.html#6">6</a>. File position not an offset unimplementable</h3>
<p><b>Section:</b> 31.5.3 <a href="https://wg21.link/fpos">[fpos]</a> <b>Status:</b> <a href="lwg-active.html#NAD">NAD</a>
 <b>Submitter:</b> Matt Austern <b>Opened:</b> 1997-12-15 <b>Last modified:</b> 2016-08-09</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View all other</b> <a href="lwg-index.html#fpos">issues</a> in [fpos].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#NAD">NAD</a> status.</p>
<p><b>Discussion:</b></p>
<p>Table 88, in I/O, is too strict; it's unimplementable on systems
where a file position isn't just an offset. It also never says just
what <code>fpos&lt;&gt;</code> is really supposed to be.  [Here's my summary, which
Jerry agrees is more or less accurate. &quot;I think I now know what
the class really is, at this point: it's a magic cookie that
encapsulates an <code>mbstate_t</code> and a file position (possibly represented as
an <code>fpos_t</code>), it has syntactic support for pointer-like arithmetic, and
implementors are required to have real, not just syntactic, support
for arithmetic.&quot; This isn't standardese, of course.] </p>


<p><b>Rationale:</b></p>
<p>Not a defect. The LWG believes that the Standard is already clear,
and that the above summary is what the Standard in effect says.</p>





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