Dave,
I'm baffled - I had no idea that the SET TIME command would update the time logicals. Hopefuly this also happens when the regular rollover to 2024 happens.
(Later) No it doesn't, as the following script shows
Code: Select all
$ type timezone_test.com
$ set time="31-dec-2023 23:59:55"
$ loop:
$ show time
$ show logical sys$timezone_rule
$ wait ::1
$ goto loop
$
$ @timezone_test.com
31-DEC-2023 23:59:55
"SYS$TIMEZONE_RULE" = "CET^1CEST^2,M3.4.0/02,M10.5.0/03" (LNM$SYSTEM_TABLE)
31-DEC-2023 23:59:56
"SYS$TIMEZONE_RULE" = "CET^1CEST^2,M3.4.0/02,M10.5.0/03" (LNM$SYSTEM_TABLE)
31-DEC-2023 23:59:57
"SYS$TIMEZONE_RULE" = "CET^1CEST^2,M3.4.0/02,M10.5.0/03" (LNM$SYSTEM_TABLE)
31-DEC-2023 23:59:58
"SYS$TIMEZONE_RULE" = "CET^1CEST^2,M3.4.0/02,M10.5.0/03" (LNM$SYSTEM_TABLE)
31-DEC-2023 23:59:59
"SYS$TIMEZONE_RULE" = "CET^1CEST^2,M3.4.0/02,M10.5.0/03" (LNM$SYSTEM_TABLE)
1-JAN-2024 00:00:00
"SYS$TIMEZONE_RULE" = "CET^1CEST^2,M3.4.0/02,M10.5.0/03" (LNM$SYSTEM_TABLE)
1-JAN-2024 00:00:01
"SYS$TIMEZONE_RULE" = "CET^1CEST^2,M3.4.0/02,M10.5.0/03" (LNM$SYSTEM_TABLE)
1-JAN-2024 00:00:02
"SYS$TIMEZONE_RULE" = "CET^1CEST^2,M3.4.0/02,M10.5.0/03" (LNM$SYSTEM_TABLE)
1-JAN-2024 00:00:03
"SYS$TIMEZONE_RULE" = "CET^1CEST^2,M3.4.0/02,M10.5.0/03" (LNM$SYSTEM_TABLE)
*Interrupt*
$
How is the logical adapted to the 2024 value if no SET TIME is issued?
That said, with the new SYS$TIMEZONE_RULE logical the DST-to-STD rule is wrong again (M10.4.0/03 instead of M10.5.0/3), but that's okay as the fourth Sunday in October 2024 will also be the last Sunday.
cu,
Martin
Added in 18 minutes 57 seconds:
Volker,
nitpicking...
volkerhalle wrote: ↑Tue Oct 31, 2023 1:04 pm
They key seems to be the following lines in SYS$COMMON:[SYS$ZONEINFO.SYSTEM.SOURCES]europe.
Code: Select all
Rule EU 1981 max - Mar lastSun 1:00u 1:00 S
Rule EU 1996 max - Oct lastSun 1:00u 0 -
But in the same file it is stated that these rules only apply to Western and Eastern Europe, while Central Europe uses the "C-Eur" rules (which state the same rules, only in local time):
Code: Select all
Rule C-Eur 1981 max - Mar lastSun 2:00s 1:00 S
Rule C-Eur 1996 max - Oct lastSun 2:00s 0 -
Zone WET 0:00 EU WE%sT
Zone CET 1:00 C-Eur CE%sT
Zone MET 1:00 C-Eur ME%sT
Zone EET 2:00 EU EE%sT
<sigh> There's a reason that the VMS FAQ dedicates a whole chapter to Time and Timekeeping....
cu,
Martin
There is something wrong with everything that is popular.
(Charles Fort)