Blindly pkilling sox is a bad idea

[megabytesofrem]

Blindly pkilling sox is a bad idea. Especially since it's possible that a user could have multiple instances of sox running, and when he/she closes Lyrebird then all of the other instances of sox get killed too. An alternative would be to look into terminating the subprocess properly

[hunternet93]

When you run subprocess.Popen, it returns a Popen object on which you can call kill() to kill its attached process. Just store a reference in your MainWindow class and add a function to run kill:

class MainWindow:
  def whatever_makes_sox(self):
    self.sox_proc = subprocess.Popen(whatever)

  def cleanup(self):
    if self.sox_prox:
      self.sox_proc.kill()

Then add a global try/except handler wrapping your Gtk.main(), for example:

try:
  Gtk.main()
except BaseException e:
  win.cleanup()

(Catching BaseException means it'll also catch KeyboardInterrupt, SystemExit, and a few others that don't inherit from Exception)

I'm not on my dev machine right now so can't make a PR, but I think that should do it.