[tz] [PROPOSED] Merge timezones that are alike since 1970

[Brian Inglis]

On 2021-06-01 17:48, Paul Eggert via tz wrote:
> These are good questions. We have the 'backzone' file for type (2) data, 
> but the 'backzone' approach is apparently unsatisfactory for some users 
> of type (2) data.
> 
> Part of the problem may be that 'backzone' is a mishmash quality-wise. 
> Today there are only two simple options in the Makefile - use either all 
> of 'backzone' or none of it - and there are real problems with using all 
> of it. Perhaps we could add something that would give users more 
> flexibility.
> 
> For example, if a downstream user wants the 'backzone' entry for 
> Europe/Stockholm which is well-documented, but doesn't want backzone's 
> America/Montreal entry because it's not well-attested and is most likely 
> wrong, the user could specify a list of backzone names that includes 
> Europe/Stockholm but excludes America/Montreal. I think it would not be 
> too much work to add something like this to the tzdb code. This would 
> better support users who want a separate Zone for each country in 
> 'backzone', but do not want all of 'backzone'.

To see what some of the major distros do, look at the comments about 
Ruby on BSDs and package build specs:

https://github.com/tzinfo/tzinfo/issues/15#issuecomment-41739379
https://github.com/freebsd/freebsd-src/tree/master/contrib/tzdata
https://svnweb.freebsd.org/ports/head/misc/zoneinfo/
https://salsa.debian.org/glibc-team/tzdata/-/tree/sid/debian
https://src.fedoraproject.org/rpms/tzdata/tree/rawhide
https://build.opensuse.org/package/show/openSUSE:Factory/timezone - view
https://github.com/bmwiedemann/openSUSE/tree/master/packages/t/timezone 
- raw download

Most distros have some localized, possibly graphical, tzsetup utility.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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