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<title>Issue 2658: [filesys.ts] [PDTS] POSIX utime() is obsolescent</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#TS">TS</a> status.</em></p>
<h3 id="2658"><a href="lwg-defects.html#2658">2658</a>. [filesys.ts] [PDTS] POSIX <code>utime()</code> is obsolescent</h3>
<p><b>Section:</b> 15.25 [filesys.ts::fs.op.last_write_time] <b>Status:</b> <a href="lwg-active.html#TS">TS</a>
 <b>Submitter:</b> LWG/SG-3 <b>Opened:</b> 2014-02-13 <b>Last modified:</b> 2017-07-30</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View all other</b> <a href="lwg-index.html#filesys.ts::fs.op.last_write_time">issues</a> in [filesys.ts::fs.op.last_write_time].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#TS">TS</a> status.</p>
<p><b>Discussion:</b></p>
<p><b>Addresses: filesys.ts</b></p>
<p>POSIX now says: "Since the <code>utimbuf</code> structure only contains <code>time_t</code> variables
and is not accurate to fractions of a second, applications
should use the <code>utimensat()</code> function instead of the obsolescent <code>utime()</code> function."</p>

  <p>
    Suggested resolution: Rewrite the <code>last_write_time</code> setter description to utilize <code>utimensat() or similar.</code>
  </p>

  <p><i>[20 May 2014 Beman Dawes supplies proposed wording. He comments:]</i></p>


  <p>POSIX supplies two functions, <code>futimens()</code> and <code>utimensat()</code>,
  as replacements for <code>utime()</code>.
  <code>futimens()</code> is appropriate for the current TS.
  <code>utimensat()</code> will be appropriate for a future File System TS that adds the
  functionality of the whole family of POSIX *<code>at()</code> functions.
</p>



<p id="res-2658"><b>Proposed resolution:</b></p>
  <p>
    <i>Change 15.25 Last write time [fs.op.last_write_time]:</i>
  </p>
  <blockquote>
    <p>
      <i>Effects:</i> Sets the time of last data modification of the file resolved
      to by <code>p</code> to <code>new_time</code>, as if by POSIX <del>
        <code>stat()</code>
        followed by POSIX <code>utime()</code>
      </del> <ins>
        <code>futimens()</code>
      </ins>.
    </p>
  </blockquote>





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