Re: date and UTC and GMT odd behaviour

[Mike 'Mike' Jones]

Yep, I tried the same on a SuSE 8.2 machine with version 4.5.8 in Germany
and I get the correct behaviour.  Unfortunately it's the only SuSE machine 
I have access to!  However, on a machine in the USA running Red Hat WS 
release 3 and data version 4.5.3, I also see the correct behaviour.

So, could it be that /etc/localtime is influencing the behaviour?

... In fact moving /etc/localtime out of the way I get the correct 
behaviour so I guess this is the route of the problem:
specifically /usr/share/zoneinfo/Europe/London on my system!

/usr/share/zoneinfo/Europe/Belfast (which is a different file but the same 
time zone) also suffers from this problem.  Paris on the other hand does 
not.

Copying /usr/share/zoneinfo/Europe/London from the SuSE machine in Germany 
and using it on my machine reproduces the problem.  So I guess it's an 
Linux OS distribution independent bug.

Humph!

Thanks,
Mike



On Tue, 23 Aug 2005, Andreas Schwab wrote:

> "Mike 'Mike' Jones" <address@hidden> writes:
>
> > A little bit of trial-and-error and I find that the anomaly is limited to
> > between 6pm, 23 Jun 1968 GMT and 2am, 31 Oct 1971:
> >
> > $ date -d "Sat Oct 31 01:59:59 UTC 1971" +%s
> > 57722399
> > $ date -d "Sat Oct 31 01:59:59 GMT 1971" +%s
> > 57718799
> >
> > $ date -d "Sat Oct 31 02:00:00 UTC 1971" +%s
> > 57722400
> > $ date -d "Sat Oct 31 02:00:00 GMT 1971" +%s
> > 57722400
> >
> > and
> >
> > $ date -d "Sun Jun 23 18:00:00 UTC 1968" +%s
> > -48060000
> > $ date -d "Sun Jun 23 18:00:00 GMT 1968" +%s
> > -48063600
> >
> > $ date -d "Sun Jun 23 17:59:59 UTC 1968" +%s
> > -48060001
> > $ date -d "Sun Jun 23 17:59:59 GMT 1968" +%s
> > -48060001
>
> I can't reproduce that here.  I get the same (correct) output whether I
> use UTC or GMT.
>
> > This means that using:
> > $ date -d "Tue Jan 01 00:00:00 GMT 1970 + NNNNN seconds"
>
> Better use date -d "@NNNNNN".
>
> Andreas.

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