terminate a linux command line utility from python

Question

I've got a command line utility from canutils called candump. It works like this:

I run candump (specifying the bus from which I want to dump)

root@beaglebone: candump can0

It then runs until I end it using CTRL+C

However, when I run it in a python script like so.

Popen(["candump","can0"],stdout=PIPE)

or

call(["candump","can0"])

I'm not sure how to end it. Any ideas?

Answer 1

Don't use use the call command if you want control over the subprocess

If you use Popen like you did above you should assign it to a variable like this:

p = Popen(["candump","can0"],stdout=PIPE)

Once you have p then you can use one of the following SIGNAL commands on it http://docs.python.org/2/library/subprocess.html#subprocess.Popen.send_signal

Answer 2

Use Popen(), and call send_signal(signal.SIGINT) on the returned Popen object.