@@ -531,33 +531,22 @@ func (srv *Server) CmdPs(stdin io.ReadCloser, stdout io.Writer, args ...string)

 func (srv *Server) CmdCommit(stdin io.ReadCloser, stdout io.Writer, args ...string) error {

 	cmd := rcli.Subcmd(stdout,

-		"commit", "[OPTIONS] CONTAINER [DEST]",

+		"commit", "[OPTIONS] CONTAINER [REPOSITORY [TAG]]",

 		"Create a new image from a container's changes")

 	if err := cmd.Parse(args); err != nil {

 		return nil

 	}

-	containerName, imgName := cmd.Arg(0), cmd.Arg(1)

-	if containerName == "" || imgName == "" {

+	containerName, repository, tag := cmd.Arg(0), cmd.Arg(1), cmd.Arg(2)

+	if containerName == "" {

 		cmd.Usage()

 		return nil

 	}

-	if container := srv.runtime.Get(containerName); container != nil {

-		// FIXME: freeze the container before copying it to avoid data corruption?

-		// FIXME: this shouldn't be in commands.

-		rwTar, err := container.ExportRw()

-		if err != nil {

-			return err

-		}

-		// Create a new image from the container's base layers + a new layer from container changes

-		img, err := srv.runtime.graph.Create(rwTar, container.Image, "")

-		if err != nil {

-			return err

-		}

-

-		fmt.Fprintln(stdout, img.Id)

-		return nil

+	img, err := srv.runtime.Commit(containerName, repository, tag)

+	if err != nil {

+		return err

 	}

-	return errors.New("No such container: " + containerName)

+	fmt.Fprintln(stdout, img.Id)

+	return nil

 }

 func (srv *Server) CmdExport(stdin io.ReadCloser, stdout io.Writer, args ...string) error {

@@ -200,6 +200,33 @@ func (runtime *Runtime) Destroy(container *Container) error {

 	return nil

 }

+// Commit creates a new filesystem image from the current state of a container.

+// The image can optionally be tagged into a repository

+func (runtime *Runtime) Commit(id, repository, tag string) (*Image, error) {

+	container := runtime.Get(id)

+	if container == nil {

+		return nil, fmt.Errorf("No such container: %s", id)

+	}

+	// FIXME: freeze the container before copying it to avoid data corruption?

+	// FIXME: this shouldn't be in commands.

+	rwTar, err := container.ExportRw()

+	if err != nil {

+		return nil, err

+	}

+	// Create a new image from the container's base layers + a new layer from container changes

+	img, err := runtime.graph.Create(rwTar, container.Image, "")

+	if err != nil {

+		return nil, err

+	}

+	// Register the image if needed

+	if repository != "" {

+		if err := runtime.repositories.Set(repository, tag, img.Id); err != nil {

+			return img, err

+		}

+	}

+	return img, nil

+}

+

 func (runtime *Runtime) restore() error {

 	dir, err := ioutil.ReadDir(runtime.repository)

 	if err != nil {