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Comment by tryauuum | Hacker News Reader

  echo {a..z} | tr ' ' '\n' | sort -R | head -1 > /proc/sysrq-trigger

this is my favourite linux russian roulette

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This echoes a letter to /proc/sysrq-trigger, with Deck of Many Fates results:

https://www.kernel.org/doc/html/v4.15/admin-guide/sysrq.html...

EDIT: Yeah, uh, it works.

Here's a variant that works in #!/bin/ash

    base64 /dev/urandom | tr -d '/+'| sed s/[^[:alpha:]]//g |tr 'A-Z' 'a-z' | dd bs=1 count=1 2>/dev/null

For a moment I was excited to learn about a new shell named ash.

https://en.wikipedia.org/wiki/Almquist_shell

Got your wish

I hate to be a golfer... buuuut this should still be pretty generic shell

    LC_ALL=C tr -dc 'a-z' </dev/urandom | head -c 1

I think you don't even need

  head -c 1

because sysrq-trigger will read only one character anyway

Nice one! I wasn't taking testing that far =)

edit - Actually I don't think it closes the input, so for an initial char that doesn't cause something fatal it looks to continue writing.

just tested -- only reads first char, at least with echo (also any character which is not used is used as "h")

  echo apm > /proc/sysrq-trigger

I'm too scared to test with your urandom stuff...

I saw that too, but in this case `echo` exits. My note was just regarding the pipeline will continue to write forever if the first character was any of the non destructive commands.

Without trashing vms...

    ( while true; do printf 'a'; done ) > /proc/sysrq-trigger

With the `head`, the output is closed.

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