@@ -1,7 +1,7 @@

 # the following lines are in sorted order, FYI

 github.com/Azure/go-ansiterm 388960b655244e76e24c75f48631564eaefade62

 github.com/Microsoft/hcsshim v0.5.17

-github.com/Microsoft/go-winio v0.4.0

+github.com/Microsoft/go-winio v0.4.1

 github.com/Sirupsen/logrus v0.11.0

 github.com/davecgh/go-spew 346938d642f2ec3594ed81d874461961cd0faa76

 github.com/docker/libtrust 9cbd2a1374f46905c68a4eb3694a130610adc62a

@@ -124,7 +124,8 @@ func (f *win32File) Close() error {

 	return nil

 }

-// prepareIo prepares for a new IO operation

+// prepareIo prepares for a new IO operation.

+// The caller must call f.wg.Done() when the IO is finished, prior to Close() returning.

 func (f *win32File) prepareIo() (*ioOperation, error) {

 	f.wg.Add(1)

 	if f.closing {

@@ -155,7 +156,6 @@ func ioCompletionProcessor(h syscall.Handle) {

 // the operation has actually completed.

 func (f *win32File) asyncIo(c *ioOperation, d *deadlineHandler, bytes uint32, err error) (int, error) {

 	if err != syscall.ERROR_IO_PENDING {

-		f.wg.Done()

 		return int(bytes), err

 	}

@@ -192,7 +192,6 @@ func (f *win32File) asyncIo(c *ioOperation, d *deadlineHandler, bytes uint32, er

 	// code to ioCompletionProcessor, c must remain alive

 	// until the channel read is complete.

 	runtime.KeepAlive(c)

-	f.wg.Done()

 	return int(r.bytes), err

 }

@@ -202,6 +201,7 @@ func (f *win32File) Read(b []byte) (int, error) {

 	if err != nil {

 		return 0, err

 	}

+	defer f.wg.Done()

 	if f.readDeadline.timedout.isSet() {

 		return 0, ErrTimeout

@@ -228,6 +228,8 @@ func (f *win32File) Write(b []byte) (int, error) {

 	if err != nil {

 		return 0, err

 	}

+	defer f.wg.Done()

+

 	if f.writeDeadline.timedout.isSet() {

 		return 0, ErrTimeout

 	}

@@ -367,6 +367,8 @@ func connectPipe(p *win32File) error {

 	if err != nil {

 		return err

 	}

+	defer p.wg.Done()

+

 	err = connectNamedPipe(p.handle, &c.o)

 	_, err = p.asyncIo(c, nil, 0, err)

 	if err != nil && err != cERROR_PIPE_CONNECTED {