[tz] Terminology mismatch in tzcode file format manpage / header

Steve Allen sla at ucolick.org
Fri May 18 01:52:19 UTC 2012

On Thu 2012-05-17T21:31:10 -0400, Andrew Paprocki hath writ:
> I was under the impression WRC-12 was discussing a proposal to
> eliminate leap seconds, redefining UTC, and that is what was tabled to
> the WRC-15 agenda.

During the past 10 years the proposals have been to change the
characteristics of the broadcast time scale while retaining the name

> Potential changes to the UTC standard do not seem relevant when
> discussing the use of both "GMT" and "UTC" in the same definition of a
> field in the tz file format.

The text of agenda item 1.14 is
    1.14 to consider the feasibility of achieving a continuous
    reference time-scale, whether by the modification of coordinated
    universal time (UTC) or some other method, and take appropriate
    action, in accordance with Resolution 653 [COM6/20] (WRC-12)
This wording invites the possibility of changing both the
characteristics and the name of the internationally-approved broadcast
time scale if that is the expedient means of achieving the change
needed for technical purposes.

It seems imprudent to change the name of the functions in the tzcode
if in three years the name of the broadcast time scale might change
to something other than UTC.

> This implies to me that "utc" should be used in the field name, to
> match the existing definition next to it which states "UTC".

Except that the implementation of zoneinfo is based on the POSIX
notion of UTC, and that is incongruent with the ITU-R notion of UTC.
This is similar to other aspects of zoneinfo where authority and
practice differ due to Byzantine bureaucratic processes run by
hot-headed folks with entrenched but opposing positions.  No action
taken by the tz list can solve the fundamental problem nor avoid
confusion in actual practice.

Steve Allen                 <sla at ucolick.org>                WGS-84 (GPS)
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