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This documentation describes considerations for consumers of the MIT krb5 libraries.</p> <p>Applications or libraries which use libkrb5 and consume the timestamps included in credentials or other structures make use of the <tt class="xref c c-type docutils literal"><span class="pre">krb5_timestamp</span></tt> type. For historical reasons, krb5_timestamp is a signed 32-bit integer, even on platforms where a larger type is natively used to represent time values. To behave properly for time values after January 2038, calling code should cast krb5_timestamp values to uint32_t, and then to time_t:</p> <div class="highlight-python"><pre>(time_t)(uint32_t)timestamp</pre> </div> <p>Used in this way, krb5_timestamp values can represent time values up until February 2106, provided that the platform uses a 64-bit or larger time_t type. This usage will also remain safe if a later version of MIT krb5 changes krb5_timestamp to an unsigned 32-bit integer.</p> <p>The GSSAPI only uses representations of time intervals, not absolute times. Callers of the GSSAPI should require no changes to behave correctly after January 2038, provided that they use MIT krb5 release 1.16 or later.</p> </div> </div> </div> </div> </div> <div class="sidebar"> <h2>On this page</h2> <ul> <li><a class="reference internal" href="#">Year 2038 considerations for uses of krb5_timestamp</a></li> </ul> <br/> <h2>Table of contents</h2> <ul class="current"> <li class="toctree-l1"><a class="reference internal" href="../user/index.html">For users</a></li> <li class="toctree-l1"><a class="reference internal" href="../admin/index.html">For administrators</a></li> <li class="toctree-l1 current"><a class="reference internal" href="index.html">For application developers</a><ul class="current"> <li class="toctree-l2"><a class="reference internal" href="gssapi.html">Developing with GSSAPI</a></li> <li class="toctree-l2 current"><a class="current reference internal" href="">Year 2038 considerations for uses of krb5_timestamp</a></li> <li class="toctree-l2"><a class="reference internal" href="h5l_mit_apidiff.html">Differences between Heimdal and MIT Kerberos API</a></li> <li class="toctree-l2"><a class="reference internal" href="init_creds.html">Initial credentials</a></li> <li class="toctree-l2"><a class="reference internal" href="princ_handle.html">Principal manipulation and parsing</a></li> <li class="toctree-l2"><a class="reference internal" href="refs/index.html">Complete reference - API and datatypes</a></li> </ul> </li> <li class="toctree-l1"><a class="reference internal" href="../plugindev/index.html">For plugin module developers</a></li> <li class="toctree-l1"><a class="reference internal" href="../build/index.html">Building Kerberos V5</a></li> <li class="toctree-l1"><a class="reference internal" href="../basic/index.html">Kerberos V5 concepts</a></li> <li class="toctree-l1"><a class="reference internal" href="../formats/index.html">Protocols and file formats</a></li> <li class="toctree-l1"><a class="reference internal" href="../mitK5features.html">MIT Kerberos features</a></li> <li class="toctree-l1"><a class="reference internal" href="../build_this.html">How to build this documentation from the source</a></li> <li class="toctree-l1"><a class="reference internal" href="../about.html">Contributing to the MIT Kerberos Documentation</a></li> <li class="toctree-l1"><a class="reference internal" href="../resources.html">Resources</a></li> </ul> <br/> <h4><a href="../index.html">Full Table of Contents</a></h4> <h4>Search</h4> <form class="search" action="../search.html" method="get"> <input type="text" name="q" size="18" /> <input type="submit" value="Go" /> <input type="hidden" name="check_keywords" value="yes" /> <input type="hidden" name="area" value="default" /> </form> </div> <div class="clearer"></div> </div> </div> <div class="footer-wrapper"> <div class="footer" > <div class="right" ><i>Release: 1.15.1</i><br /> © <a href="../copyright.html">Copyright</a> 1985-2017, MIT. </div> <div class="left"> <a href="../index.html" title="Full Table of Contents" >Contents</a> | <a href="gssapi.html" title="Developing with GSSAPI" >previous</a> | <a href="h5l_mit_apidiff.html" title="Differences between Heimdal and MIT Kerberos API" >next</a> | <a href="../genindex.html" title="General Index" >index</a> | <a href="../search.html" title="Enter search criteria" >Search</a> | <a href="mailto:krb5-bugs@mit.edu?subject=Documentation__Year 2038 considerations for uses of krb5_timestamp">feedback</a> </div> </div> </div> </body> </html>