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[](https://gitter.im/HowardHinnant/date?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+
+IMPORTANT UPDATE:
+Recently IANA changed how they reported the database version. If you have `AUTO_DOWNLOAD` enabled in the tz library, you must update to include this commit:
+
+https://github.com/HowardHinnant/date/commit/19c83e47ed411a45e0b5a45d772c47c6ee23ac3f
+
+Without this update your tz lib will download a new copy of the database everytime you start your program.
+
_**[Try it out on wandbox!](http://melpon.org/wandbox/permlink/lb6FHxHyQ1V9eCLm)**_
This is actually several separate C++11/C++14 libraries:
@@ -12,8 +20,9 @@ This is actually several separate C++11/C++14 libraries:
2. `"tz.h"` / `"tz.cpp"` are a timezone library built on top of the `"date.h"` library. This timezone library is a complete parser of the IANA timezone database. It provides for an easy way to access all of the data in this database, using the types from `"date.h"` and ``. The IANA database also includes data on leap seconds, and this library provides utilities to compute with that information as well. See http://howardhinnant.github.io/date/tz.html for more details.
- There was a talk on this library at
- [Cppcon 2016](https://cppcon2016.sched.org/event/7nLc/welcome-to-the-time-zone). The slides are [here](http://schd.ws/hosted_files/cppcon2016/0f/Welcome%20To%20The%20Time%20Zone%20-%20Howard%20Hinnant%20-%20CppCon%202016.pdf).
+ Here is the Cppcon 2016 presentation on tz.h: https://www.youtube.com/watch?v=Vwd3pduVGKY
+
+ Here are the Cppcon 2016 slides on tz.h: http://schd.ws/hosted_files/cppcon2016/0f/Welcome%20To%20The%20Time%20Zone%20-%20Howard%20Hinnant%20-%20CppCon%202016.pdf
3. `"chrono_io.h"` is a header-only library for streaming out chrono durations. See http://howardhinnant.github.io/date/chrono_io.html for more details.