Cfrgtkky

I want to get the date information with this command:

date --date=2019-03-22

or

date --date=2019/03/22

but it shows this error:

date: invalid date ‘2019-03-22’

or

 date: invalid date ‘2019/03/22’

as you can see it is not related to dash. the same thing happens with slash.

When I use another date like

date --date=2019-03-21

It shows the information correctly.

It shouldn't be related to the bad dash character. because I just deleted the last 2 and replaced it with 1 and the output is OK.

What is going wrong?

Result of some commands for more information:

$ date --version

date (GNU coreutils) 8.28

Copyright (C) 2017 Free Software Foundation, Inc.

License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.

This is free software: you are free to change and redistribute it.

There is NO WARRANTY, to the extent permitted by law.



Written by David MacKenzie.

$ type -a date

date is /bin/date

$ uname -m

x86_64

$ lsb_release -a

No LSB modules are available.

Distributor ID: Ubuntu

Description:    Ubuntu 18.04.2 LTS

Release:    18.04

Codename:   bionic

$ which date

/bin/date

$ apt-cache policy coreutils

coreutils:

  Installed: 8.28-1ubuntu1

  Candidate: 8.28-1ubuntu1

  Version table:

 *** 8.28-1ubuntu1 500

        500 http://us.archive.ubuntu.com/ubuntu bionic/main amd64 Packages

        100 /var/lib/dpkg/status

$ date

Fri Mar 22 06:54:59 PDT 2019

date --date=2019-03-22 2>&1 | od -c

0000000   d   a   t   e   :       i   n   v   a   l   i   d       d   a

0000020   t   e     342 200 230   2   0   1   9   -   0   3   -   2   2

0000040 342 200 231  n

0000044

Something weird going on with different timezone in this date: 2019-03-22. I randomly changed timezone to different areas. Some of them have errors, some of them not! When I select these I have problem with that specific date:

• Los Angeles (USA)


• Shanghai (China)


• Madrid (Spain)


• Tehran (Iran)

I'm almost sure this is due to the changeover to Daylight Saving Time in the given timezone: effectively this means that an hour "disappears" (and hence becomes "invalid").

In my own timezone, DST started at 2AM on Sunday 10th March, so that hour is invalid:

$ cat /etc/timezone

America/Toronto

$ date --date="2019-03-10 02:00:00"

date: invalid date ‘2019-03-10 02:00:00’

whereas the times immediately before and after are valid:

$ date --date="2019-03-10 01:59:59"

Sun Mar 10 01:59:59 EST 2019



$ date --date="2019-03-10 03:00:00"

Sun Mar 10 03:00:00 EDT 2019

In timezones where the change over happens at midnight, the bare date appears invalid because GNU date assumes a time of midnight:

$ TZ=Asia/Tehran date --date='2019-03-22'

date: invalid date ‘2019-03-22’

but one hour later is valid:

$ TZ=Asia/Tehran date --date='2019-03-22 01:00:00'

Fri Mar 22 01:00:00 +0430 2019

See also Invalid Date Linux

$ date_ascii="2019-03-22"

$ printf "%s" "$date_ascii" | od -c

0000000   2   0   1   9   -   0   3   -   2   2

0000012

$ TZ=Asia/Shanghai date -d "$date_ascii"

Fri Mar 22 00:00:00 America 2019

and

$ date_unicode="2019‑03‑22"

$ printf "%s" "$date_unicode" | od -c

0000000   2   0   1   9 342 200 221   0   3 342 200 221   2   2

0000016

$ TZ=Asia/Shanghai date -d "$date_unicode"

date: invalid date ‘2019‑03‑22’