@@ -127,7 +127,7 @@ func (daemon *Daemon) Attach(container *Container, stdin io.ReadCloser, stdinClo

 	)

 	if stdin != nil && container.Config.OpenStdin {

-		nJobs += 1

+		nJobs++

 		if cStdin, err := container.StdinPipe(); err != nil {

 			errors <- err

 		} else {

@@ -163,7 +163,7 @@ func (daemon *Daemon) Attach(container *Container, stdin io.ReadCloser, stdinClo

 		}

 	}

 	if stdout != nil {

-		nJobs += 1

+		nJobs++

 		if p, err := container.StdoutPipe(); err != nil {

 			errors <- err

 		} else {

@@ -201,7 +201,7 @@ func (daemon *Daemon) Attach(container *Container, stdin io.ReadCloser, stdinClo

 		}()

 	}

 	if stderr != nil {

-		nJobs += 1

+		nJobs++

 		if p, err := container.StderrPipe(); err != nil {

 			errors <- err

 		} else {

@@ -252,7 +252,7 @@ func (daemon *Daemon) Attach(container *Container, stdin io.ReadCloser, stdinClo

 		// FIXME: how to clean up the stdin goroutine without the unwanted side effect

 		// of closing the passed stdin? Add an intermediary io.Pipe?

-		for i := 0; i < nJobs; i += 1 {

+		for i := 0; i < nJobs; i++ {

 			log.Debugf("attach: waiting for job %d/%d", i+1, nJobs)

 			if err := <-errors; err != nil {

 				log.Errorf("attach: job %d returned error %s, aborting all jobs", i+1, err)

@@ -908,7 +908,7 @@ func (b *buildFile) Build(context io.Reader) (string, error) {

 		} else if b.rm {

 			b.clearTmp(b.tmpContainers)

 		}

-		stepN += 1

+		stepN++

 	}

 	if b.image != "" {

 		fmt.Fprintf(b.outStream, "Successfully built %s\n", utils.TruncateID(b.image))