'Spawn a process and its watchers.'

def _spawn(self):

    self._is_running = True
    self._pid = None
    self._kill_event = eventlet.event.Event()
    (self._process, cmd) = utils.create_process(self._cmd, run_as_root=self.run_as_root)
    self._watchers = []
    for reader in (self._read_stdout, self._read_stderr):
        watcher = eventlet.spawn(self._watch_process, reader, self._kill_event)
        self._watchers.append(watcher)
