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using stdout of a node in a launch file

asked 2016-10-07 07:26:57 -0500

Sietse gravatar image

I would like to use the output of a command in a launch file. Think of the back quote notatie is the shell: hostname So for example something like

<arg name="robotname" default="`hostname`" />

With the idea that the value of robotname is the hostname of the machine.

How could this functionality be achieved?

Thanks in advance, Sietse

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answered 2016-10-07 07:59:28 -0500

mgruhler gravatar image

You would need to write this yourself.

Currently, you can only get environment variables, which would work for the hostname

<arg name="robotname" default="$(env HOSTNAME)/>

The wiki page states that (for kinetic) eval

allows to evaluate arbitrary complex python expressions

but I don't know what this actually means. Maybe this would allow you to work a way around this.

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Thanks! Thats it.

Sietse gravatar image Sietse  ( 2016-10-07 08:20:40 -0500 )edit

answered 2016-10-07 07:57:33 -0500

Airuno2L gravatar image

Can you pass the output in through an arg somehow?

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Asked: 2016-10-07 07:26:57 -0500

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Last updated: Oct 07 '16