'L{PIDFile.isRunning} raises L{StalePIDFileError} for a process that
does not exist (errno=ESRCH).'

@ifPlatformSupported
def test_isRunningDoesNotExist(self):

    pidFile = PIDFile(DummyFilePath())
    pidFile._write(1337)
    def kill(pid, signal):
        raise OSError(errno.ESRCH, 'No    such    process')
    self.patch(_pidfile, 'kill', kill)
    self.assertRaises(StalePIDFileError, pidFile.isRunning)
