[tz] leap-seconds.list format

[brian.inglis at systematicsw.ab.ca]

On 2024-02-08 07:21, Martin Burnicki via tz wrote:
> Byron Torres via tz wrote:
>> Thank you, Steve, Paul, Martin, Brian, Tim for your informative
>> responses, resources and clarifications.
>>
>> On Wed Feb 7, 2024 at 3:03 PM GMT, Brian Inglis wrote:
>>> IIRC the leap-seconds.list file loosely follows the format used by NTP for
>>> digital security certificate files generated by ntp-keygen.
>>
>> Interesting.
>>
>> On Wed Feb 7, 2024 at 5:04 PM GMT, Tim Parenti wrote:
>>> The other data files distributed by tzdb have long been tab/space-agnostic,
>>> so our general response is that parsers should be, too.
>>
>> Seems like the way forward for Hare.
>>
>> I was hoping to coordinate a formal definition of the current informal
>> format, defined apart from the file as a separate document, perhaps even
>> an RFC, or even for a newer format.
>>
>> However, the file format seems sensible and stable enough currently,
>> and I am satisfied with moving on.
> 
> I've put an informational page together which provides some basic information on 
> the NTP leap second file:
> https://kb.meinbergglobal.com/kb/time_sync/ntp/configuration/ntp_leap_second_file
> 
> At the bottom of the page there are links to the original paper which introduces 
> the leap second file, and ways to use it.
> 
> The paper explains the suggested file format, but it doesn't tell whether the 
> white space between data fields should (or must) be tabs or spaces.
> 
> Please note that some special fields like the expiration date were introduced 
> later.
> 
> So my previous suggestion remains:
> 
> - Ignore all comment lines except the special ones starting with "#$", "#@", or 
> "#h", which have special meanings.
> 
> - Treat tabs or spaces between data fields in the same way, as field separators.

Also, considering the rules for sha1 hash generation and validation, and this is 
likely to continue to be the case if a better modern hash is added, only the 
numeric digits in the uncommented portions and special comment lines should be 
considered significant data: everything else is documentation for human 
consumption only.

-- 
Take care. Thanks, Brian Inglis              Calgary, Alberta, Canada

La perfection est atteinte                   Perfection is achieved
non pas lorsqu'il n'y a plus rien à ajouter  not when there is no more to add
mais lorsqu'il n'y a plus rien à retirer     but when there is no more to cut
                                 -- Antoine de Saint-Exupéry