[tz] Hard copy of TZdata2023?

[Brian Inglis]

On 2023-10-20 11:27, Alexandre Petrescu via tz wrote:
> Le 15/10/2023 à 02:28, natyaveda via tz a écrit :
>> Hey, are you aware of any printable or hard copy (paper) publications of your 
>> Time-Zone database in a complete or semi-complete form?
>> Perhaps this has been produced by someone in the astrology community?
>> I'm basically looking to see if its possible to get the rights to include 
>> parts of such a publication in a publication of my own.  I doubt one exists 
>> that includes all the info for every city in the world in a single 
>> publication, but I'm looking to see if it does and how large it might be.
>> What I have in mind is something that lists information pretty much exactly as 
>> its presented in the tables for the "Detailed time zone and clock changes" 
>> available on timeanddate.com (minus everything outside the tables):
>> <https://www.timeanddate.com/time/zone/canada/vancouver>

 > I am looking to obtain approximately the same.
> The full database might be too much to print and read. But a concise form
> of it, on an A4 or letter sized paper, might be useful. It should be
> updateable easily, every few months or so. It should contain the capitals and
> major cities worldwide. Should not contain the past history info. Should
> list the names in alphabetical order, and with several spellings (local
> spelling first). It should tell the date of the next few DST changes. Should
> be printed in a large font. Should be used when Internet is not available. > Other than that hard copy, I am also interested to be notified by email
> about the single next DST change that will happen at a site worldwide (not
> only at my place). For example, I think now the next DST change (no DST) is
> going to happen in Europe in November, but not sure whether there are others
> before that.
I have defined a zdump alias for interactive use (below) which searches 
backwards for the first transition in the given zone (or local time) from this 
year, displaying them up to the start of next year (whose data is not included 
in any output), which you may be able to adapt by iterating thru all zones of 
interest, which could just be symlinks to zoneinfo in some directory as in the 
examples at the top of the shell commands and output.

And seriously *hardcopy*, in this century (other than for tax backups, which are 
still based on Roman technology)?!
At least generate markdown or html which can be displayed locally in a browser, 
or converted to a digital document using pandoc, htmldoc, or similar.
Then you can run this generation process whenever a new tz release is detected 
automatically, so it is always up to date.

# zdump interesting zones using alias or script then post-process
$ ln -st ./interested/ /usr/share/zoneinfo/Europe/Brussels ...	# symlink zones
$ for tz in ./interested/*; do zdump $tz; done | process	# output zones

$ which zdump	# interactive alias
zdump ()
{
     local z=${@:-${TZ:-/etc/localtime}} y=$(date +%Y);
     local e=$(($y+1)) b p l t;

     for b in $y 1970 1900 1752;
     do
         range=-Vc$b,$e;
         p=$(command /usr/bin/zdump $range $z);
         [ -n "$p" ] && break;
     done;

     l=${p##*'
'};
     t=${l##*[012][0-9]:[0-5][0-9]:[0-6][0-9] };
     b=${t:0:4};

     if [ -n "$b" ]; then
         range=-Vc$b,$e;
         [ $b -lt $y ] && p=$(command /usr/bin/zdump $range $z);
     else
         range='';
         p=$(command /usr/bin/zdump $range $z);
     fi;

     [ -n "$range" ] && echo zdump $range $z;

     echo "$p"
}

# zdump alias example outputs

$ zdump Europe/Brussels
zdump -Vc2023,2024 Europe/Brussels
Europe/Brussels  Sun Mar 26 00:59:59 2023 UT = Sun Mar 26 01:59:59 2023 CET 
isdst=0 gmtoff=3600
Europe/Brussels  Sun Mar 26 01:00:00 2023 UT = Sun Mar 26 03:00:00 2023 CEST 
isdst=1 gmtoff=7200
Europe/Brussels  Sun Oct 29 00:59:59 2023 UT = Sun Oct 29 02:59:59 2023 CEST 
isdst=1 gmtoff=7200
Europe/Brussels  Sun Oct 29 01:00:00 2023 UT = Sun Oct 29 02:00:00 2023 CET 
isdst=0 gmtoff=3600

$ zdump
zdump -Vc2023,2024 America/Edmonton
America/Edmonton  Sun Mar 12 08:59:59 2023 UT = Sun Mar 12 01:59:59 2023 MST 
isdst=0 gmtoff=-25200
America/Edmonton  Sun Mar 12 09:00:00 2023 UT = Sun Mar 12 03:00:00 2023 MDT 
isdst=1 gmtoff=-21600
America/Edmonton  Sun Nov  5 07:59:59 2023 UT = Sun Nov  5 01:59:59 2023 MDT 
isdst=1 gmtoff=-21600
America/Edmonton  Sun Nov  5 08:00:00 2023 UT = Sun Nov  5 01:00:00 2023 MST 
isdst=0 gmtoff=-25200

$ zdump America/Regina
zdump -Vc1960,2024 America/Regina
America/Regina  Sun Apr 24 08:59:59 1960 UT = Sun Apr 24 01:59:59 1960 MST 
isdst=0 gmtoff=-25200
America/Regina  Sun Apr 24 09:00:00 1960 UT = Sun Apr 24 03:00:00 1960 CST 
isdst=0 gmtoff=-21600

-- 
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