1.. _implementation-defined-behavior: 2 3=============================== 4Implementation-defined behavior 5=============================== 6 7Contains the implementation details of the implementation-defined behavior in 8libc++. Implementation-defined is mandated to be documented by the Standard. 9 10.. note: 11 This page is far from complete. 12 13 14Implementation-defined behavior 15=============================== 16 17Updating the Time Zone Database 18------------------------------- 19 20The Standard allows implementations to automatically update the 21*remote time zone database*. Libc++ opts not to do that. Instead calling 22 23 - ``std::chrono::remote_version()`` will update the version information of the 24 *remote time zone database*, 25 - ``std::chrono::reload_tzdb()``, if needed, will update the entire 26 *remote time zone database*. 27 28This offers a way for users to update the *remote time zone database* and 29give them full control over the process. 30 31Listed in the index of implementation-defined behavior 32====================================================== 33 34The order of the entries matches the entries in the 35`draft of the Standard <http://eel.is/c++draft/impldefindex>`_. 36