[tz] TZ Changing in Chile on May, 14th.

Paul Eggert eggert at cs.ucla.edu
Tue May 3 19:59:14 UTC 2016

On 05/02/2016 04:08 PM, Luis Martinez Villa wrote:
>   Can you please explain me how these structures in tzdata2016c work 
> to accomplish the necessary TZ change in Chile.

Before the transition, this rule line is active:

Rule    Chile    2012    2014    -    Sep    Sun>=2 4:00u    1:00    S

so Chile is assumed to be on daylight saving time, i.e., -03. You can 
verify this by running 'zdump -c2016,2017 -v America/Santiago'. Its 
output should contain:

America/Santiago  Sun May 15 02:59:59 2016 UT = Sat May 14 23:59:59 2016 
CLST isdst=1 gmtoff=-10800
America/Santiago  Sun May 15 03:00:00 2016 UT = Sat May 14 23:00:00 2016 
CLT isdst=0 gmtoff=-14400

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