Getting stdio process ID

Questions & Help Questions
6

@rvirding it’s possible to do something similar to this but with :stdio?

    Process.unregister(:standard_error)
    {:ok, dev} = StringIO.open("")
    Process.register(dev, :standard_error)
    Code.eval_file(exercise, File.cwd!) |> elem(0)
    captured = StringIO.flush(dev)
    Process.unregister(:standard_error)
    Process.register(original_stderr, :standard_error)

to capture :stdio output in a variable?