[solved] Are shutdown and init command the same?

[deepakdeshp]

Hello,
What is the difference between following commands? Which should be used preferably?

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sudo init 0
sudo shutdown 0

[kc1di]

Hello,
in mint 18.3 init was replaced by systemd as default and unless you've purposefully changed the boot system init commands are no longer needed.
simply

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sudo shutdown -h now

for shutdown or

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 sudo shutdown -r now

for restart will suffice. there are no run levels in systemd , but they are called targets.
you can read more here: https://unix.stackexchange.com/question ... nux-server read the section starting at <86>

[Mute Ant]

"Are shutdown and init command the same?" Not exactly the same no...
md5sum $(which init) $(which shutdown)
520afdca7fd55654f737f5f07e2327c4 /sbin/init
e3b947f8c0c716efdb20f84be19e67fb /sbin/shutdown
...although in Mint 17.3 they both come from package upstart
apt-get source upstart

[all41]

systemctl poweroff

[Sir Charles]

systemctrl poweroff

Thanks for this!
I had keyboard shortcuts for suspend and hibernate. The trio is now complete

[all41]

There is also systemctl reboot
systemd is new turf

[Sir Charles]

I am running out of key-combinations
Thanks!

[all41]

Check out
yelp man:systemctl

[Sir Charles]

systemctl --kill-who=
LOL
Cheers

[all41]

just to acknowledge op deepakdeshp's question remains unanswered here.
I do not know the answer

[AZgl1800]

Hello,
What is the difference between following commands? Which should be used preferably?

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sudo init 0
sudo shutdown 0

init 0 is old and outdated: https://askubuntu.com/questions/75427/u ... n-computer

you don't need 'sudo' for shutdown 0, I use it everyday to shut my laptop down to avoid the keyring damen coming up and making my shutdowns greatly extended.

I just simply do Control-ALT-T and type in 'shutdown 0' and every thing is gracefully closed and down it goes. now.

I am using:
Kernel: 4.13.0-26-generic x86_64 (64 bit)
Desktop: Cinnamon 3.6.7 Distro: Linux Mint 18.3 Sylvia

[rene]

What is the difference between following commands? Which should be used preferably?

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sudo init 0
sudo shutdown 0

The second, although not with unadorned 0 but with either +0 or its alias now; the fact that 0 works at all is essentially a parser bug. The sudo is not necessary either: being an administrator user (which on Mint means being root and/or a member of groups "sudo" and/or "admin") will make polkit grant permission to shutdown the system. Among the two given choices shutdown now is the preferred command, then.

The init program used to in not so olden times be the name of the actual system init, the program launched by the kernel directly so as to create process 1, the init process. The telinit program was used to communicate with said process and specifically telinit <number> would instruct said process to switch to runlevel <number>. telinit moreover used to in fact simply be a link to init with the program deciding at runtime whether to behave as init or as telinit simply by seeing if it was in fact process 1 or not.

These days init is itself a link to /lib/systemd/systemd but systemd emulates the above behaviour: init 0 is still equivalent to telinit 0 and the latter you in man telinit find to be in turn equivalent to systemctl poweroff; like before, sudo is not in fact necessary. shutdown is a link to systemctl with the systemctl program at runtime deciding how to behave depending on what name it was called through. In the case of that name being "shutdown" it behaves exactly as, again, systemctl poweroff.

This is to say that while in the end there's no difference between the presented choices, the preferred command should in fact be systemctl poweroff. Your options are two levels of historical baggage...

[all41]

Hello,
What is the difference between following commands? Which should be used preferably?

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sudo init 0
sudo shutdown 0

@rene
Yes, I agree.
Yet Mint 17.3 is still in support and systemd solutions are not an option for Mint 17.3 users.
I think op wants to know how running services are terminated in each instance?
@deepakdeshp please ring back in here.

[rene]

Yet Mint 17.3 is still in support and systemd solutions are not an option for Mint 17.3 users. I think op wants to know how running services are terminated in each instance?

In case you have disabled display of signatures: he specifically mentions to be running Mint 18.3 in it. No mention of 17 anywhere so I do believe he's asking simply in the Mint 18 context. Anyways...

In Mint 17 init used to be upstart rather than systemd but the "same" as above holds in the sense of both init 0 and shutdown -h now being equivalent to telinit 0; to init switching the system to runlevel 0. I do believe that leaving out -h in that case in fact meant telinit 1 instead, single-user mode. And you do need sudo on 17.

In even older sysvinit days shutdown was or could be supplied by util-linux and was at the very least conceptually different from telinit 0 in the sense of it signalling processes itself. It of course depended on a specific distribution's implementation of going to runlevel 0 whether or not that was actually all that different, and I seem to recall not all distributions using the util-linux shutdown back then. Slackware I fully trust did the most obsolete thing it could think of and used the util-linux one directly, but if I'm not mistaken RedHat for example did not; if not simply misremembering then I trust they in fact implemented it as telinit 0.

[kc1di]

to answer the original question.
In a multi user system under init if you issue init 0 the system will go down without any notification where using shutdown -h will send a message to anyone on the system that the system is about to go down. so shutdown is delayed a bit.

But it was a good discussion and provided lots of info for other to consider.

[rene]

to answer the original question. In a multi user system under init if you issue init 0 the system will go down without any notification where using shutdown -h will send a message to anyone on the system that the system is about to go down. so shutdown is delayed a bit.

If by "under init" you specifically mean "not under systemd" then fine but note this to be untrue for Mint 18.3 which is what the poster runs. On it, shutdown -h now goes down as fast and as quietly as init 0 (although "as quietly" might judging from the manpages in fact be unintended).

Don't get it. Why do both you and all41 assume the question is not about Mint 18? There's no mention of anything other than Mint 18.3 and hence of systemd.

[kc1di]

to answer the original question. In a multi user system under init if you issue init 0 the system will go down without any notification where using shutdown -h will send a message to anyone on the system that the system is about to go down. so shutdown is delayed a bit. Th

If by "under init" you specifically mean "not under systemd" then fine but note this to be untrue for Mint 18.3 which is what the poster runs. On it, shutdown -h now goes down as fast and as quietly as init 0 (although "as quietly" might judging from the manpages in fact be unintended).

Don't get it. Why do both you and all41 assume the question is not about Mint 18? There's no mention of anything other than Mint 18.3 and hence of systemd.

that is why I Specifically said Under init - If you look at my first post you will see I told the op that 18.3 runs under systemd and that there are no run levels in that system. Cheers

[deepakdeshp]

That's an excellent discussion , thanks all. And yes I do use Mint 18.3 and the context to my question is 18.3.
I learnt many things. Systems is quite involved, I don't intend to read something voluminous. Does anybody know a link or slideshow explaining the basics of systemd?

[rene]

https://www.digitalocean.com/community/ ... he-journal looks useful.

I would however primarily suggest man pages. In this case ls -l $(which init) followed by man systemd would for example inform you that

For compatibility with SysV, if systemd is called as init and a PID that is not 1, it will execute telinit and pass all command line arguments unmodified. That means init and telinit are mostly equivalent when invoked from normal login sessions. See telinit(8) for more information.

and the subsequent man telinit that init 0 is hence ...

[ ... ] translated into an activation request for poweroff.target and is equivalent to systemctl poweroff.

Other than an init system systemd is much more these days; be sure to separate the two (ha! two!) when studying it.

[kc1di]

That's an excellent discussion , thanks all. And yes I do use Mint 18.3 and the context to my question is 18.3.
I learnt many things. Systems is quite involved, I don't intend to read something voluminous. Does anybody know a link or slideshow explaining the basics of systemd?

This page is pretty good and concise.
https://www.digitalocean.com/community/ ... he-journal
and you can always get the basic command structure by entering

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man systemd

in the terminal.
Happy learning