I can not understand the command from the systemd?

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alekseev
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I can not understand the command from the systemd?

Post by alekseev » Sun Jul 22, 2018 8:32 am

journalctl --since "tomorrow"

By idea to show magazines from tomorrow. As it is illogical.
Tell me what is the essence of the team with the key tomorrow?

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Pierre
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Re: I can not understand the command from the systemd?

Post by Pierre » Sun Jul 22, 2018 8:40 am

you will need to give some extra information,
before anyone is able to assist you:

- what version of LinuxMint are you using ?.
- what were you doing, when running that particular command ?.
:)
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Please edit your original post title to include [SOLVED] - when your problem is solved!
and DO LOOK at those Unanswered Topics - - you may be able to answer some!.

gm10
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Re: I can not understand the command from the systemd?

Post by gm10 » Sun Jul 22, 2018 8:47 am

or maybe more to the point, what are you trying to achieve with that command. --since "tomorrow" is a nonsensical option since it will only show log entries from tomorrow, i.e. it won't show you anything, unless your computer is a time machine. :lol:

rene
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Re: I can not understand the command from the systemd?

Post by rene » Sun Jul 22, 2018 10:00 am

gm10 wrote:
Sun Jul 22, 2018 8:47 am
--since "tomorrow" is a nonsensical option [ ... ]
That is probably exactly what he means; i.e., he seems to be inquiring after possible uses for the "tomorrow" date specifier in the context of journalctl.

Clearly "--since tomorrow" is useless at least when considered in the context of someone sitting at a shell and typing in the journalctl command; it does make marginal sense for "--until", i.e., journalctl --since today --until tomorrow, but that in itself would seem to be provided for more compactly simply by journalctl --since today since the missing --until defaults to "now", and we can still be quite certain in advance that no log entries from between now and tomorrow will be present at any given invocation time.

I've tried to imagine scheduled, delayed invocations and what not -- but frankly I'm coming up blank. Might be the type of thing where you just need one example to go "aaah" but for now I expect that the 'tomorrow" specifier is either there basically just as a result of the time parsing function being used in a wider context than just journalctl, including ones in which it does make sense, or as a result of the basic programmer mistake of confusing symmetry with truth...

Still, nice question/observation :)

gm10
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Re: I can not understand the command from the systemd?

Post by gm10 » Sun Jul 22, 2018 10:16 am

rene wrote:
Sun Jul 22, 2018 10:00 am
Still, nice question/observation :)
I'm not sure I agree. I could also do --since +24h. Just because it parses doesn't mean you aren't responsible for what you put there.

rene
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Re: I can not understand the command from the systemd?

Post by rene » Sun Jul 22, 2018 10:22 am

Sure, but the question in this case and in the specific context of journalctl becomes what are even possible uses for the "tomorrow" date specifier, i.e., why is it present at all? As said, wider context for the parsing function or sillymetry might be the answer; am myself still not coming up with better reasons...

gm10
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Re: I can not understand the command from the systemd?

Post by gm10 » Sun Jul 22, 2018 10:29 am

rene wrote:
Sun Jul 22, 2018 10:22 am
Sure, but the question in this case and in the specific context of journalctl becomes what are even possible uses for the "tomorrow" date specifier, i.e., why is it present at all? As said, wider context for the parsing function or sillymetry might be the answer; am myself still not coming up with better reasons...
Theoretical use cases are if you specify the -f option and want it to start/end in the future. I can't think of anything else. Even those are fringe cases, my guess is the programmer just saw no reason to limit the time parser function (which he probably lifted from somewhere else, anyway).

rene
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Re: I can not understand the command from the systemd?

Post by rene » Sun Jul 22, 2018 10:33 am

Mmm. Actually, yes, makes enough sense in the context of -f for me; had overlooked that, thanks. Shall go watch Netflix again then....

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