Ruder Laplace <ruder.em...@gmail.com> wrote: > Greetings, > > I think I catched a bug related to the day-light saving gap: > *uname -a ; date ; date -d "2020/06/01 10:00:00 +1 hours"* > Linux ******** 4.19.0-8-amd64 #1 SMP Debian 4.19.98-1 (2020-01-26) x86_64 > GNU/Linux > mié nov 25 10:30:29 CET 2020 > lun jun 1 *12*:00:00 CEST 2020 > > As far as I think it should work, the expected result should be: lun jun 1 > *11*:00:00 CEST 2020 > "One hour after 10" is 11, not 12.
You can check how date interprets your string using --debug: $ date -d "2020/06/01 11:00:00 +1 hour" --debug date: warning: value 2020 has 4 digits. Assuming YYYY/MM/DD date: parsed date part: (Y-M-D) 2020-06-01 date: parsed time part: 11:00:00 UTC+01 date: parsed relative part: +1 hour(s) date: input timezone: parsed date/time string (+01) date: using specified time as starting value: '11:00:00' date: starting date/time: '(Y-M-D) 2020-06-01 11:00:00 TZ=+01' date: '(Y-M-D) 2020-06-01 11:00:00 TZ=+01' = 1591005600 epoch-seconds date: after time adjustment (+1 hours, +0 minutes, +0 seconds, +0 ns), date: new time = 1591009200 epoch-seconds date: timezone: system default date: final: 1591009200.000000000 (epoch-seconds) date: final: (Y-M-D) 2020-06-01 11:00:00 (UTC) date: final: (Y-M-D) 2020-06-01 13:00:00 (UTC+02) Mo 1. Jun 13:00:00 CEST 2020 As you can see, it assumes that the "+1" indicates the timezone, which is 1 hour behind your local zone, thus 11:00 there would actually be 12:00 in your time zone. The "hour" alone is then used as a +1 hour adjustment, resulting in 13:00 CEST. Commands that work as you expected: $ date -d "2020/06/01 11:00:00 1 hour" --debug $ date -d "2020/06/01 11:00:00 +1 +1 hour" --debug $ date -d "2020/06/01 11:00:00 CEST +1 hour" --debug $ date -d "+1 hour 2020/06/01 11:00:00" --debug rainer
