What happens to at jobs across the DST switch?

[Karl Auer]

On Fri, 2021-03-26 at 22:12 +0100, Bo Berglund wrote:
> echo "timeout --signal=2 66m getstreamyt testutc.mp4" | at 22:58 UTC
> 
> But it shows up in the list as:
> 
> 2250    Fri Mar 26 22:58:00 2021 a bosse
> 
> Should have been (since I am in CET zone):
> 2250    Fri Mar 26 23:58:00 2021 a bosse

kauer at kt1:~$ at 2:10 UTC today
warning: commands will be executed using /bin/sh
at> date >> /tmp/at.txt
at> <EOT>
job 9 at Sat Mar 27 12:10:00 2021
kauer at kt1:~$ atq
9	Sat Mar 27 12:10:00 2021 a kauer
kauer at kt1:~$ date
Sat 27 Mar 2021 12:10:09 AEDT
kauer at kt1:~$ cat /tmp/at.txt
Sat 27 Mar 2021 12:10:00 AEDT

Well, it sort of worked for me - except that it seems to think UTC is
10 hours behind me, when at the moment UTC is 11 hours behind!

I specified "2:10 UTC today" and it produced a job for 12:10 local
time. The UTC modifier definitely worked at some level. It looks as if
"at" is mishandling timezone, because my system gets it right:

kauer at kt1:~$ date -u ; date
Sat 27 Mar 2021 01:17:54 UTC
Sat 27 Mar 2021 12:17:54 AEDT

If it is mishandling UTC for you as well, and is likewise out by one
hour, then that explains why you get no difference between UTC and non-
UTC - CET is only an hour ahead of UTC at the moment.

Regards, K.


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Karl Auer (kauer at biplane.com.au)
http://www.biplane.com.au/kauer

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