'Stale PID file is removed without causing a system exit.'

def test_stale(self):

    pidfile = self.mktemp()
    with open(pidfile, 'w') as f:
        f.write(str((os.getpid() + 1)))
    def kill(pid, sig):
        raise OSError(errno.ESRCH, 'fake')
    self.patch(os, 'kill', kill)
    checkPID(pidfile)
    self.assertFalse(os.path.exists(pidfile))
