[tz] zic option to generate smaller output files?

[Paul Eggert]

Ken Murchison wrote:
> Would it also be possible to have this option (or a separate one) create the 
> first header and body (32-bit time values) with counts of zero?

That'd be a change to the format, since the intent (as I understand it) is for 
the 32- and 64-bit parts to agree for timestamps in 32-bit range. (Although this 
isn't written down; it should be.) So this should be a separate zic option.

I expect 32-bit clients typically look only at the 32-bit part and would misfire 
if it were omitted, so if we added a zic option to generate such a format it 
would surely not be the default at first. Still, it would make sense to add the 
option, as 32-bit clients will become obsolete in a couple of decades anyway, 
and we might as well get the ball rolling.