# EFS backup and restore

This sample app demonstrates how to use APIs to request EFS backup and listen to EFS restore and backup indications.

1. Get platform factory instance

auto &platformFactory = telux::platform::PlatformFactory::getInstance();
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2. Prepare a callback that is invoked when the filesystem sub-system initialization is complete

std::promise<telux::common::ServiceStatus> p;
    auto initCb = [&p](telux::common::ServiceStatus status) {
       std::cout << "Received service status: " << static_cast<int>(status) << std::endl;
       p.set_value(status);
    };
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3. Get the filesystem manager

std::shared_ptr<telux::platform::IFsManager> fsManager = platformFactory.getFsManager(initCb);
    if (fsManager == nullptr) {
       std::cout << "filesystem manager is nullptr" << std::endl;
       exit(1);
    }
    std::cout << "Obtained filesystem manager" << std::endl;
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4. Wait until initialization is complete

p.get_future().get();
    if (fsManager->getServiceStatus() != telux::common::ServiceStatus::SERVICE_AVAILABLE) {
       std::cout << "Filesystem service not available" << std::endl;
       exit(1);
    }
    std::cout << "Filesystem service is now available" << std::endl;
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5. Create the listener object and register as a listener

std::shared_ptr<EfsEventListener> efsEventListener = std::make_shared<EfsEventListener>();
    fsManager->registerListener(efsEventListener);
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6. Receive service status notifications

virtual void onServiceStatusChange(telux::common::ServiceStatus serviceStatus) override {
       PRINT_NOTIFICATION << "Filesystem service status: ";
       std::string status;
       switch (serviceStatus) {
          case telux::common::ServiceStatus::SERVICE_AVAILABLE: {
                status = "Available";
                break;
          }
          case telux::common::ServiceStatus::SERVICE_UNAVAILABLE: {
                status = "Unavailable";
                break;
          }
          case telux::common::ServiceStatus::SERVICE_FAILED: {
                status = "Failed";
                break;
          }
          default: {
                status = "Unknown";
                break;
          }
       }
       std::cout << status << std::endl;
    }
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7. Start EFS backup whenever necessary

telux::common::Status status = fsManager->startEfsBackup();
    if(status != telux::common::Status::SUCCESS) {
       std::cout << "Unable to start EFS backup: ";
       Utils::printStatus(status);
    }
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8. Receive EFS restore and backup notifications

virtual void OnEfsRestoreEvent(telux::platform::EfsEventInfo event) override {
       PRINT_NOTIFICATION
          << ": Received efs event: Restore"
          << ((event.event == telux::platform::EfsEvent::START) ? " started" : "ended");
       if (event.event == telux::platform::EfsEvent::END) {
          std::cout << " with result: " << Utils::getErrorCodeAsString(event.error) << std::endl;
       }
    }
    
    virtual void OnEfsBackupEvent(telux::platform::EfsEventInfo event) override {
       PRINT_NOTIFICATION
          << ": Received efs event: Backup"
          << ((event.event == telux::platform::EfsEvent::START) ? " started" : "ended");
       if (event.event == telux::platform::EfsEvent::END) {
          std::cout << " with result: " << Utils::getErrorCodeAsString(event.error) << std::endl;
       }
    }
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9. Clean-up when we do not need to listen anything

fsManager->deregisterListener(efsEventListener);
    efsEventListener = nullptr;
    fsManager = nullptr;
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Last Published: Aug 05, 2026

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