How to exec a process and keep reading it's stdout and stderr?

[aztack]

I'm currently creating an app which is just a GUI frontend of a cli exe. So I need to exec that cli executable and keep read it's stdout and write it to a . Is that possible in Niva with <code>Niva.api.process.exec</code>? Could you kindly give me an example code or show me the right way to do that?