[comp.databases] Daylight Savings Time

zed@mdbs.uucp (Bill Smith) (08/17/90)

The rule for daylight savings time can change frequently and it is
different in different countries.  There are some files on a Sun
(plus other machines I assume) that describe some of the rules.

In addition, there are areas in the US that do not observe daylight
savings time.  The greater part of Indiana is one of them.  (The
northwest and southwest corners of the state do observe daylight
savings time.)

The more general you want to be, the more difficult the problem becomes.

Bill Smith
{sawmill|pur-ee}!mdbs!zed

barr@frog.UUCP (Chris Barr) (08/19/90)

In article <1990Aug16.190228.25744@mdbs.uucp>, zed@mdbs.uucp (Bill Smith) writes:
> In addition, there are areas in the US that do not observe daylight
> savings time.  The greater part of Indiana is one of them.  (The
> northwest and southwest corners of the state do observe daylight
> savings time.)
> 
> The more general you want to be, the more difficult the problem becomes.

I've heard that a Posix document definitively defines daylight/standard 
issues - available from ..?


Chris Barr
!necntc!frog!barr

zed@mdbs.uucp (Bill Smith) (08/23/90)

>The rule for daylight savings time can change frequently and it is
>different in different countries.  There are some files on a Sun
>(plus other machines I assume) that describe some of the rules.

This information is in the directory /usr/lib/zoneinfo.

>In addition, there are areas in the US that do not observe daylight
>savings time.  The greater part of Indiana is one of them.  (The
>northwest and southwest corners of the state do observe daylight
>savings time.)

According to the information in /usr/lib/zoneinfo, Arizona is another
part of the US that does not observe daylight savings time.  Also, some
of the different Indian Nations within the U.S. apparently may follow 
different policies.

Some parts of the world (especially in wartime) observe double daylight
savings time (where the clock is shifted 2 hours).

The rules for the normal parts of the US are that it changes at
2AM on the first Sunday of April and 2AM on the last Sunday of October.
(I think someone else has said this part already.)

Bill Smith
pur-ee!mdbs!zed