Fast dom0 -> Qube commands

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1

Hello,

I am searching the fastest way to execute a command from Dom0 to a Qube with the following requirements:

  • exit code is important (I must know the command fail)
  • stdout / stderr is irrelevant
  • should still be secure
  • should be fast

Right now on my machine, this invocation is 180~270ms:
qvm-run disp777 /bin/true

I am wondering if I can use directly qrexec-client as I know it is very much faster (this is 10~20ms):
qrexec-client -tT -d deb-dvm 'user:exec /bin/true' > /dev/null 2>&1

But is it secure ?

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2

hi,

could it be possible for you to describe what you want to achieve? Maybe you are going in the wrong direction, and it could be done in a better way.

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3

Hello Solene,

I am looking to integrate my i3wm bindings with my emacs bindings as described on Getting a consistent set of keybindings between i3 and Emacs and Another Emacs i3 Integration - Wai Hon's Blog.

Speed of execution is critical because directly felt for many little interactions.

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4

I’m not aware of any difference security wise, except that qvm-run would by default color stdout/stderr red if they’re going to a terminal (which of course in your case they don’t anyway, because you’re redirecting both to /dev/null) to make this untrusted data easier to distinguish from the rest of the terminal session.

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