// has reached zero, i.e when all the readers have given up their locks.
type RLockedFile struct {
	*LockedFile
	mutex sync.Mutex
	refs  int // Holds read lock refs.
}

// IsClosed - Check if the rlocked file is already closed.
func (r *RLockedFile) IsClosed() bool {
	r.mutex.Lock()
	defer r.mutex.Unlock()
	return r.refs == 0
}

// IncLockRef - is used by called to indicate lock refs.
func (r *RLockedFile) IncLockRef() {

			t.Fatal(err)
		}
	}()

	rlk, err := RLockedOpenFile(f.Name())
	if err != nil {
		t.Fatal(err)
	}
	isClosed := rlk.IsClosed()
	if isClosed {
		t.Fatal("File ref count shouldn't be zero")
	}

	// Increase reference count to 2.
	rlk.IncLockRef()

	isClosed = rlk.IsClosed()
	if isClosed {
		t.Fatal("File ref count shouldn't be zero")
	}

	// Decrease reference count by 1.

	case debugSetClientPingDuration:
		c.clientPingInterval = args[0].(time.Duration)
	case debugAddToDeadline:
		c.addDeadline = args[0].(time.Duration)
	case debugIsOutgoingClosed:
		// params: muxID uint64, isClosed func(bool)
		muxID := args[0].(uint64)
		resp := args[1].(func(b bool))
		mid, ok := c.outgoing.Load(muxID)
		if !ok || mid == nil {
			resp(true)
			return
		}
		mid.respMu.Lock()