// runs a command in a container , with volume mounted
// returns completion code.
// exits (t.Fatal() or create/start/wait errors
func runContainerCmd(t *testing.T, client *client.Client, volumeName string,
	image string, cmd *strslice.StrSlice, addr string) int {

	mountPoint := getMountpoint(volumeName)
	bind := volumeName + ":" + mountPoint
	t.Logf("Running cmd=%v with vol=%s on client %s", cmd, volumeName, addr)

	r, err := client.ContainerCreate(context.Background(),
		&container.Config{Image: image, Cmd: *cmd,
			Volumes: map[string]struct{}{mountPoint: {}}},
		&container.HostConfig{Binds: []string{bind}}, nil, "")
	if err != nil {
		t.Fatalf("\tContainer create failed: %v", err)
	}

	err = client.ContainerStart(context.Background(), r.ID,
		types.ContainerStartOptions{})
	if err != nil {
		t.Fatalf("\tContainer start failed: id=%s, err %v", r.ID, err)
	}

	code, err := client.ContainerWait(context.Background(), r.ID)
	if err != nil {
		t.Fatalf("\tContainer wait failed: id=%s, err %v", r.ID, err)
	}

	if removeContainers == false {
		t.Logf("\tSkipping container removal, id=%s (removeContainers == false)",
			r.ID)
		return code
	}

	err = client.ContainerRemove(context.Background(), r.ID,
		types.ContainerRemoveOptions{
			RemoveVolumes: true,
			Force:         true,
		})
	if err != nil {
		t.Fatalf("\nContainer removal failed: %v", err)
	}

	return code
}