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I want to shutdown my computer as if power was cut off (don't ask me why). How do I do this under Linux?

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migrated from Sep 30 '10 at 20:18

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Pull the power plug? :) – Bryan Sep 30 '10 at 20:10
And you know that there's a difference between "init 6" and cutting the power off?! You should decide which of your two questions you want to be answered. – AndiDog Sep 30 '10 at 20:13
@Bryan: Won't work on a laptop, so you'd also have to remove the battery. – David Thornley Sep 30 '10 at 20:15
I meant init 0. I can't edit the question. – Alexandru Sep 30 '10 at 20:39
up vote 7 down vote accepted

If your system has it, the poweroff command should do it:

poweroff -n -f

  -n = don't sync
  -f = don't run shutdown
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Interesting, but my man page for poweroff doesn't list -n (not that it's needed). – TomMD Sep 30 '10 at 20:17
My man page for poweroff does list these options :-). Debian squeeze/stable. – sleske Feb 14 '11 at 23:18

you can echo 'o' (poweroff) to /proc/sysrq-trigger:

$ echo o | sudo tee /proc/sysrq-trigger
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This is one of the better options if your hard disks failed. In such a case, you'll get an I/O error running the poweroff command. – i_grok Nov 16 '12 at 18:09

you could just panic it, depending on what you wish to achieve.

sysctl -w kernel.panic=1
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That's even better than I had in mind. – Alexandru Sep 30 '10 at 20:40

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