@@ -550,6 +550,10 @@ func pullImageIfNotExist(image string) (err error) {

 	return

 }

+func dockerCmdWithError(c *check.C, args ...string) (string, int, error) {

+	return runCommandWithOutput(exec.Command(dockerBinary, args...))

+}

+

 func dockerCmd(c *check.C, args ...string) (string, int) {

 	out, status, err := runCommandWithOutput(exec.Command(dockerBinary, args...))

 	c.Assert(err, check.IsNil, check.Commentf("%q failed with errors: %s, %v", strings.Join(args, " "), out, err))