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Daylight Savings (again!)

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matthew robey
Frequent Advisor

Daylight Savings (again!)

Ok, so down here (down under), we have the Commonwealth Games happening at the end of March.
The government have decided that as the majority of TV viewers won't be in Oz or NZ, the change to daylight savings will be a week later than normal.(So the Poms don't have to get up too early!).This has of course nothing to do with money generated by TV advertising.

Anyway, what do I need to do (if anything) to change the automatic daylight savings to kick in on the first Sunday in April, rather than the last Sunday in March.

OpenVms V7.3-2, tpip V5.4, no DTSS, Decnet V over tcpip, auto_dlight_sav set to 1.


Matt (who is both Pom and Aussie)
Thomas Ritter
Respected Contributor

Re: Daylight Savings (again!)

Matthew, we have our OPS make the changes using command procedures. We run VMS 7.3-2 and RDB. From an application point of view only some aspects uses dates stored as data. RDB use sequence numbers so it won't break.
I would ensure that time offsets are used. Experience has show that if OPS key in times manually say using a set time command then they might get the year, month or all wrong.
After considering the applications affects and I would submit a batch job using something similar to our MENU scripts.

An extract from our script is this

$ current_time = f$cvtime()
$ current_time_plus_one_hour = f$cvtime("+01:00")
$ current_time_minus_one_hour = f$cvtime("-01:00")
$ clearx
$ ws bold + "This Procedure will set the time FORWARDS by exactly one hour from NOW" + normal
$ ask "''f$fao("Confirm change of time !/!_from !AS !/!_to !AS (y/n) ",current_time,current_time_plus_one_hour)'" ans
$ if ans
$ then
$ if f$getsyi("CLUSTER_MEMBER")
$ then
$ ws bold + "$ set time/cluster=''current_time_plus_one_hour'" + normal
$ set time="+01:00"/cluster
$ ws bold + f$fao("Current system time on the Cluster is !%D",0) + normal
$ else
$ ws bold + "$ set time=''current_time_plus_one_hour'" + normal
$ set time="+01:00"
$ ws bold + f$fao("Current system time !%D",0) + normal
$ endif
$ request/to=security "''f$getjpi("","USERNAME")' has changed the SYSTEM TIME Forwards."
$ else
$ ws tab + "Request terminated."
$ endif

Andy Bustamante
Honored Contributor

Re: Daylight Savings (again!)

See chapter 6 of the System Manager's Manual vol 1 and sys$examples:DAYLIGHT_SAVINGS.COM. You'll need to change auto_dlight_sav to 0 (and reboot) to prevent the automatic change. http://h71000.www7.hp.com/doc/732FINAL/aa-pv5mh-tk/aa-pv5mh-tk.HTMl

If you don't have time to do it right, when will you have time to do it over? Reach me at first_name + "." + last_name at sysmanager net
Ian Miller.
Honored Contributor

Re: Daylight Savings (again!)

See VMS FAQ section 4.4.1
Purely Personal Opinion
matthew robey
Frequent Advisor

Re: Daylight Savings (again!)

In case there are any other Aussies who want to know:

Modified the AUSTRALASIA file in

added the following line under NSW

Rule AN 2006 only - Apr Sun>=1 2:00 0 -

Then $ zic -v -d sys$common:[sys$zoneinfo.system] australasia
(note the space between ] and australasia)

Then @sys$manager:utc$time_setup

And the logical "SYS$TIMEZONE_RULE" = "EST-10EST-11,M10.5.0/02,M4.1.0/03"

So in theory all should be sweet for April.

Thanks for your help.

John Gillings
Honored Contributor

Re: Daylight Savings (again!)


Please log a case. There's an updated timezone rule "patch" for Australiasia. It may eventually make its way out to the Sydney CSC FTP site.
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