rok commented on pull request #10457: URL: https://github.com/apache/arrow/pull/10457#issuecomment-867632744
> > 3. download it from IANA Time Zone Database at runtime - `tz.h` gets the database at runtime, but curl (and 7-zip on windows) are required. > Would a 5th option to allow runtime configuration be possible as well? (which I assume would need some modification to tz.h?) I think we mean the same with 3. and 5.? I don't think modification to `tz.hz` is required. There are [`get_tzdb`](https://github.com/apache/arrow/blob/master/cpp/src/arrow/vendored/datetime/tz.cpp#L3510) and [`reload_tzdb`](https://github.com/apache/arrow/blob/master/cpp/src/arrow/vendored/datetime/tz.cpp#L3496) available for runtime. These could be interesting in cases where timezone database changes while the process is running. > For me that's fine. But to be explicit, it is currently using the default configuration of tz.h (which is to download the latest version)? I would maybe use the `USE_OS_TZDB` compile flag for now, if we postpone the discussion of how to install the tzdata sources for a follow-up JIRA. [By default](https://github.com/apache/arrow/blob/master/cpp/src/arrow/vendored/datetime/tz.h#L49) we have `USE_OS_TZDB=1` on non-windows and `USE_OS_TZDB=1` on windows. I believe that means on non-windows we download if possible and fall back to OS network is not available. On windows we currently fail. Please check as I might have misunderstood. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org
