<div dir="ltr">Just as an aid to verifying this, could you tell us which copy of the data you're using (as each file contains two or three copies of the information).<div><br></div><div>A hex dump of the relevant section would be really handy, too.</div><div><br></div><div>Jon</div><div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On 13 August 2015 at 17:21, Eric Erhardt <span dir="ltr"><<a href="mailto:Eric.Erhardt@microsoft.com" target="_blank">Eric.Erhardt@microsoft.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<p class="MsoNormal">I am working on enabling the .NET TimeZoneInfo class to read time zone information from tzfiles.<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal">I’ve hit a snag with the latest tzdata 2015f. (I’m not sure when this change started, but the problem doesn’t occur with the tzfiles that are shipped with an Ubuntu 14.04 distribution.)<u></u><u></u></p>
<p class="MsoNormal">The problem is that the 2015f version of the tzdata contains an initial "Transition Time" that is out of order. The beginning of the America/Chicago tzfile looks like the following:<u></u><u></u></p>
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<p class="MsoNormal" align="center" style="text-align:center"><b><span style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#333333">Transition Time<u></u><u></u></span></b></p>
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<p class="MsoNormal" align="center" style="text-align:center"><b><span style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#333333">Transition Offset<u></u><u></u></span></b></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#333333;background:yellow">01/01/1970 00:00:00<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#333333;background:yellow">-05:50:36<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#333333">11/18/1883 18:00:00<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#333333">-06:00:00<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#333333">03/31/1918 08:00:00<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#333333">-05:00:00 DST<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#333333">10/27/1918 07:00:00<u></u><u></u></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#333333">-06:00:00<u></u><u></u></span></p>
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<p class="MsoNormal">Notice the first entry is for 1970, and then the next entry is for 1883. This breaks the documentation in 'man tzfile':<u></u><u></u></p>
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The above header is followed by tzh_timecnt four-byte values of type long, <b>sorted in ascending order</b>. These values are written in "standard" byte order. Each is used as a transition time (as returned by time(2)) at which the rules for computing local
time change.<u></u><u></u></p>
<p class="MsoNormal">This causes the TimeZoneInfo parsing code to throw an exception because it is assuming these transitions are sorted in ascending order.<u></u><u></u></p>
<p class="MsoNormal">Is this an intentional change in the tzfiles? If so, will the tzfile man page be updated for this change?<span class="HOEnZb"><font color="#888888"><u></u><u></u></font></span></p><span class="HOEnZb"><font color="#888888">
<p class="MsoNormal">Eric Erhardt<u></u><u></u></p>
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