linuxmemes

Okay this is cool and all, but why would systemd have a calendar?

(also how do i do this)

Oh fuck. I'll use this from now on. Except for if I won't use it next week. Then I'll forget about it because my memory is a damn sieve.

me: systemd is not that bloated

systemd:

Usually such things have a simple explanation. systemd does a lot with time and date, for example scheduling tasks. It's quite obvious that it has this capabilities, when you think about it.

systemd is a great operating system, it just lacks a decent text editor.

Thanks! I hate this. 🖤

systemd is the future, and the future has been here for over a decade and yet old Unix and BSD purists still cry about it

I have one simple thing to say to the downvoters: I am not using a minicomputer from 1970, why should I be bound by the limits set then?

In the UK, if Christmas or New Year falls on a weekend, a seperate equivalent holiday is made during the week to compensate.

That's pretty clever.

Finally we can put all the controversy around systemd to rest.

Well. I mean, that's pretty cool. I don't think I would have ever guess that was an actual function from systemd but here we are

This plays some kind of role in the debate of systemd being good or not. I'm not sure if goes in the good column or the bad column, but I know it goes into a column.

Well, systemd developers made one of the classic blunders a software developer can do: make a program that has to deal with time and dates. Every time I have to deal with timestamps I'm like "oh shit, here we go again".

Anyway, as I understood it the reason this is in systemd is because they wanted to replace cron, and it's fine by me because cron has it's own brain-hurt. (The cron syntax is something that always makes me squint real hard for a while.)

This is basically just a way nicer, more flexible cron syntax being dressed up as something ridiculous. There are legitimate reasons for wanting something like this, like running some sort of resource heavy disk optimization the first Friday evening of every month or something.

It is literally happening this year.

24th is Tuesday. 1st of January is Wednesday and as a bonus Jan 6 is also a holiday in my country and that's Monday.

So from dec 22 to jan 6 i can be home by using just 6 days off

God, I only have one question...

Why?

Damn and does it work as an init too? xD.

$ systemd-analyze calendar tomorrow
Failed to parse calendar specification 'tomorrow': Invalid argument
Hint: this expression is a valid timestamp. Use 'systemd-analyze timestamp "tomorrow"' instead?
$ systemd-analyze timestamp tuesday
Failed to parse "tuesday": Invalid argument
Hint: this expression is a valid calendar specification. Use 'systemd-analyze calendar "tuesday"' instead?

ಠ_ಠ

$ for day in Mon Tue Wed Thu Fri Sat Sun; do TZ=UTC systemd-analyze calendar "$day 02-29"|tail -2; done
    Next elapse: Mon 2044-02-29 00:00:00 UTC
       From now: 19 years 4 months left
    Next elapse: Tue 2028-02-29 00:00:00 UTC
       From now: 3 years 4 months left
    Next elapse: Wed 2040-02-29 00:00:00 UTC
       From now: 15 years 4 months left
    Next elapse: Thu 2052-02-29 00:00:00 UTC
       From now: 27 years 4 months left
    Next elapse: Fri 2036-02-29 00:00:00 UTC
       From now: 11 years 4 months left
    Next elapse: Sat 2048-02-29 00:00:00 UTC
       From now: 23 years 4 months left
    Next elapse: Sun 2032-02-29 00:00:00 UTC
       From now: 7 years 4 months left

(It checks out.)

Surprisingly its calendar specification parser actually allows for 31 days in every month:

$ TZ=UTC systemd-analyze calendar '02-29' && echo OK || echo not OK
  Original form: 02-29
Normalized form: *-02-29 00:00:00
    Next elapse: Tue 2028-02-29 00:00:00 UTC
       From now: 3 years 4 months left
OK
$ TZ=UTC systemd-analyze calendar '02-30' && echo OK || echo not OK
  Original form: 02-30
Normalized form: *-02-30 00:00:00
    Next elapse: never           
OK
$ TZ=UTC systemd-analyze calendar '02-31' && echo OK || echo not OK
  Original form: 02-31
Normalized form: *-02-31 00:00:00
    Next elapse: never           
OK
$ TZ=UTC systemd-analyze calendar '02-32' && echo OK || echo not OK
Failed to parse calendar specification '02-32': Invalid argument
not OK

No Christmas for 5 years?? Why are you doing this to us, systemd???

That's actually really cool!