// Remote device on `worker2`.
  const char remote_device[] = "/job:localhost/replica:0/task:2/device:CPU:0";
  // `ctx_0`, `ctx_1` contains `remote_device`.
  {
    const std::vector<std::string>& device_names = ListDeviceNames(ctx_0);
    ASSERT_TRUE(std::find(device_names.begin(), device_names.end(),
                          remote_device) != device_names.end());
  }

  {

    const DeviceType& device_type) {
  TF_ASSIGN_OR_RETURN(tsl::StatusOr<xla::PjRtClient*> pjrt_client,
                      tensorflow::GetPjRtClient(device_type));
  auto* pjrt_c_api_client = dynamic_cast<xla::PjRtCApiClient*>(*pjrt_client);
  if (pjrt_c_api_client == nullptr) {
    return absl::InternalError(absl::StrCat("PjRtClient for ",
                                            device_type.type_string(),

  const string composite_device_name =
      "/job:localhost/replica:0/task:0/device:COMPOSITE:0";
  EXPECT_EQ(TFE_TensorHandleDeviceName(packed_handle, status),
            composite_device_name);
  EXPECT_EQ(TFE_TensorHandleBackingDeviceName(packed_handle, status),
            composite_device_name);
  ASSERT_EQ(TF_GetCode(status), TF_OK) << TF_Message(status);

}

func runDevice(appdir, bundleID string, args []string) error {
	attempt := 0
	for {
		// The device app path reported by the device might be stale, so retry
		// the lookup of the device path along with the lldb launching below.
		deviceapp, err := findDeviceAppPath(bundleID)
		if err != nil {
			// The device app path might not yet exist for a newly installed app.
			if attempt == 5 {
				return err
			}
			attempt++

      tensorflow::DeviceType(device_type), std::move(*pjrt_client));
  status->status = s;
}

void TF_ResetPjRtCClient(const char* device_type, TF_Status* status) {
  status->status =
      tensorflow::ResetPjRtClient(tensorflow::DeviceType(device_type));
}

PJRT_Client* TF_GetPjRtCClient(const char* device_type, TF_Status* status) {

func main() {
	udids := getLines(exec.Command("idevice_id", "-l"))
	if len(udids) == 0 {
		fail("no udid found; is a device connected?")
	}

	mps := detectMobileProvisionFiles(udids)
	if len(mps) == 0 {
		fail("did not find mobile provision matching device udids %q", udids)
	}

	fmt.Println("# Available provisioning profiles below.")
	fmt.Println("# NOTE: Any existing app on the device with the app id specified by GOIOS_APP_ID")

  const char remote_device_name[] =
      "/job:localhost/replica:0/task:1/device:CPU:0";
  auto* h0_task1 =
      TFE_TensorHandleCopyToDevice(h0_task0, ctx, remote_device_name, status);
  ASSERT_EQ(TF_OK, TF_GetCode(status)) << TF_Message(status);
  auto* h1_task1 =
      TFE_TensorHandleCopyToDevice(h1_task0, ctx, remote_device_name, status);
  ASSERT_EQ(TF_OK, TF_GetCode(status)) << TF_Message(status);

# Prepare fake disks with losetup
function prepare_block_devices() {
	set -e
	mkdir -p ${WORK_DIR}/disks/ ${WORK_DIR}/mnt/
	sudo modprobe loop
	for i in 1 2 3 4; do
		dd if=/dev/zero of=${WORK_DIR}/disks/img.${i} bs=1M count=2000
		device=$(sudo losetup --find --show ${WORK_DIR}/disks/img.${i})
		sudo mkfs.ext4 -F ${device}
		mkdir -p ${WORK_DIR}/mnt/disk${i}/
		sudo mount ${device} ${WORK_DIR}/mnt/disk${i}/

};
using OwnedTFBuffer = std::unique_ptr<TF_Buffer, TFBufferDeleter>;

class CGraphOptimizer : public CustomGraphOptimizer {
 public:
  explicit CGraphOptimizer(TP_Optimizer optimizer, const char* device_type)
      : optimizer_(optimizer), device_type_(device_type) {
    if (optimizer.create_func != nullptr) {
      c_optimizer_ = (*optimizer_.create_func)();
    } else {
      c_optimizer_ = nullptr;
    }
  }

                                    Tensor* tensor);

absl::StatusOr<xla::PjRtCApiClient*> GetPjRtCApiClient(
    const DeviceType& device_type);

absl::Status ResetPjRtClient(const DeviceType& device_type);

}  // namespace tensorflow