[tz] Fwd: Bulletin C number 58

Judah Levine Judah.Levine at nist.gov
Mon Jul 29 14:03:46 UTC 2019

Dear Colleagues,
   I have removed the trailing spaces that you noticed and the new files
are now posted at both ftp locations. With all due respect and with no
offense intended, I suggest that software that is sensitive to trailing
whitespace should be re-considered.
   The comment lines are intended to be helpful for any poor soul who is
not familiar with the various time formats and the definition of leap
seconds. I consider that stuff to be helpful explanations and not data.
The point of making them comments is that they could be easily ignored
by the usual software that parses scripts and by users who understand
all of the strange and wondrous details of UTC.
   I designed the two "special" comment lines so that they could be
found by reading the first two characters on every line in the file
without parsing every line. Also, they would not have to be at any
special line number in the file. I did not invent this idea -- UNIX
scripts use the same method to identify the shell. For example, a script
that did not care about the checksum could ignore that value without any
special processing.
   I invented the file format in the dark ages based on what I thought
would be useful at the time. I will *consider* improvements or changes
with the understanding that the file is used on many different and
incompatible operating systems. Any "improvement" that breaks this
requirement is unlikely to be useful.

Best wishes,

Judah Levine

On 7/29/2019 7:01 AM, Clive D.W. Feather wrote:
> Chris Woodbury via tz said:
>> Back in the dark ages, when I first started writing C code, it was said that
>> the ultimate documentations was the code.
> "If the code and the comments disagree, they're probably both wrong."

Judah Levine
Time and Frequency Division
NIST Boulder

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