[tz] [PATCH] tzdata: Asia/Ha_Noi: Add new timezone

Robert Elz kre at munnari.OZ.AU
Fri Oct 3 09:44:22 UTC 2014

It doesn't matter what is the capital, or what the official time zone
name happens to be - tz database zone names are derived from the name
of the city with the biggest population in an area (often country) that
uses the same time.

For Vietnam, every reference I can find puts Ho Chi Minh City as being more
populated than Ha Noi.   Hence Ho_Chi_Minh is the name that is used.

It is the same reason that we use Shanghai (not Beijing), and New_York (not

Even if Ha Noi's population should overtake Ho Chi Minh City it would
take a long time before we would change the name, now it has been
selected - eg: For India we still use Kolkata, even though Mumbai and Delhi
seem to have gone (way) past it in population count.   Kolkata (when we
called it Calcutta) was chosen, and remains...

Unless you can show that Ha Noi and Ho Chi Minh City have not used the
same local time for some period (a few minutes would be enough) since 1970
an additional zone won't be created for it either.   (Differences before
1970 could just possibly be used, sometime in the future, so research into
actyal time usage back into history is always useful - if backed by good


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