topic Re: Timezone settings 7.3-2 in Operating System - OpenVMS

Timezone settings 7.3-2

Richard Leighton — Tue, 05 Apr 2005 12:50:42 GMT

Hi all,

Have read the timezone threads however ...

Would anyone be able to confirm whether there is any conflict between what the timezone differential is set to and what the rule specifies.

e.g. from UTC$TIME_SETUP show

AUTO_DLIGHT_SAV is set to "0" and DTSS is not in use. You will have to manually change to/from Daylight Saving Time.

You can do this by executing SYS$MANAGER:UTC$TIME_SETUP.COM,
or you can use YS$EXAMPLES:DAYLIGHT_SAVING.COM.

LOCAL TIME ZONE = JAMAICA -- DAYLIGHT TIME
LOCAL SYSTEM TIME = 4-APR-2005 22:14:59.93(EDT)
TIME DIFFERENTIAL FACTOR = -5:00
TIME ZONE RULE = EST5EDT4,M4.1.0/02,M10.5.0/02

Change EST to EDT on the First Sunday of April (3-Apr-2005) at 02:00
Change EDT to EST on the Last Sunday of October (30-Oct-2005) at 02:00

Jamiaca does not use daylight saving however the TIME ZONE RULE "EST5EDT4,M4.1.0/02,M10.5.0/02" is specified.

We have issues with an inhouse applcaition which started to our knowledge about the time of the expected EDT change.

Performing a reboot automatically changed the sys$timezone_daylight_saving to "1" therefore the sys$timezone_name is now "EDT". The SYS$TIMEZONE_DIFFERENTIAL is still set to -18000 (GMT-5) instead of the timezone rule specification of GMT-4.

Could this cause a conflict?

DTSS is not used and DECNET-osi is not installed.

The GMT time and database current time are set as we would expect so there doesnt seem to be an issue with times.

Does Java 1.4.1 have its own timezone settings? (the application uses this).

Thanks in advance
Rich

Re: Timezone settings 7.3-2

Lawrence Czlapinski — Tue, 05 Apr 2005 13:20:11 GMT

Rich, since Jamaica doesn't use daylight saving the TIMEZONE RULE should not have different times. You may want to rerun SYS$MANAGER:UTC$TIME_SETUP.COM making them the same time differential.
As a workaround you could modify the rule to be EST5EDT5... in the .COM file. The .COM filenames were given in a recent daylight savings time related thread.
Since AUTO_DLIGHT_SAV is set to "0" and DTSS is not in use, the SYS$TIMEZONE_DIFFERENTIAL won't change till you run SYS$MANAGER:UTC$TIME_SETUP.COM
or SYS$EXAMPLES:DAYLIGHT_SAVING.COM.
So the SYS$TIMEZONE_DIFFERENTIAL should stay at GMT-5 forever unless you manually run UTC$TIME_SETUP.COM.
Lawrence

Re: Timezone settings 7.3-2

Richard Leighton — Tue, 05 Apr 2005 13:30:00 GMT

Hi Lawrence,

So it seems that even if you have a rule which is different to the actual timezone in the country as long as you don't imlplement the timezone differential factor change there should be no effect on the system. I assume that the
SYS$TIMEZONE_NAME & SYS$TIMEZONE_DAYLIGHT_SAVING logical values are just informational to inform the user whether EST or EDT is currently in use.

Thanks for your quick response
Rich

Re: Timezone settings 7.3-2

Richard Leighton — Tue, 12 Apr 2005 05:34:38 GMT

Hi All,

Please could someone tell me what the different components of the timezone rule are:

e.g.

EET-2EEST-3,M4.5.5/00,M9.5.5/00

EET-2EEST-3 - these describe Standard time (GMT-2) and daylight savings time (GMT-3).

M4.5.5/00

I know M4 is the month APR

Please could someone advise as to the .5.5/00?

Thanks
Rich

Re: Timezone settings 7.3-2

Richard Leighton — Tue, 12 Apr 2005 06:01:51 GMT

No worries I found it in the Compaq C
Run-Time Library Reference Manual for OpenVMS Systems.

Thanks