[BUGS] Don't get caught this sunday with no DST changes

[Edwin Groothuis]

On Thu, Mar 27, 2008 at 08:09:13PM +1100, jonathan michaels wrote:
> > At http://www.mavetju.org/weblog/html/00223.html I have a write up
> > on how to see if your systems need updating for coming Sundays
> > absence of DST changes.
> 
> i noticed some odd things in teh 00223.html page
> 
> $ wget ftp://ftp://elsie.nci.nih.gov/pub/tzdata2008X.tar.gz

That double ftp:// happens if you blindly copy and paste :-)

> the front bit seems to be a typo, yes ?? and teh actual name of
> teh relevent file is tzdata2008b.tar.gz

I didn't use the "b" because it changes so often and it will thus
be obsolete in three weeks anyway.

> then i did teh usual zic and copied files and when i tried to
> check teh date/time going forward i discovered something odd
> for example,

You did check if the time *before* was incorrect, didn't you?

> 
> $ perl -e 'use POSIX;print "Date = ", POSIX::ctime(1206529200 + 86400 * 0);'
> Date = Wed Mar 26 22:00:00 2008
> 
> $ perl -e 'use POSIX;print "Date = ", POSIX::ctime(1206529200 + 86400 * 7);'
> Date = Wed Apr  2 22:00:00 2008
> 
> $ perl -e 'use POSIX;print "Date = ", POSIX::ctime(1206529200 + 86400 * 14);'
> Date = Wed Apr  9 21:00:00 2008
> 
> i thought i'd gotten it nailed but then i tried the last one
> and saw the 21:00:00, again.  just to check if it is not an
> anomily i also tried one at 28 days, as well as using the shell
> scripts one liners as per provided examples.

That's the expected result: It should be 22:00 on the second wednesday
and 21:00 in the third wednesday.

Edwin

-- 
Edwin Groothuis      |            Personal website: http://www.mavetju.org
edwin at mavetju.org    |              Weblog: http://www.mavetju.org/weblog/