harmony 鸿蒙@ohos.usbManager (USB Manager)

  • 2025-06-12
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@ohos.usbManager (USB Manager)

The usbManager module provides USB device management functions, including USB device list query, bulk data transfer, control transfer, and permission control on the host side as well as USB interface management, and function switch and query on the device side.

NOTE

The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.

Modules to Import

import { usbManager } from '@kit.BasicServicesKit';

usbManager.getDevices

getDevices(): Array<Readonly<USBDevice>>

Obtains the list of USB devices connected to the host. If no device is connected, an empty list is returned. When the developer mode is disabled, undefined may be returned if no device is connected. Check whether the return value of the API is empty.

System capability: SystemCapability.USB.USBManager

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
801 Capability not supported.

Return value

Type Description
Array<Readonly<USBDevice>> USB device list.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
console.log(`devicesList = ${devicesList}`);
/*
The following is a simple example of the data structure for devicesList:
[
  {
    name: "1-1",
    serial: "",
    manufacturerName: "",
    productName: "",
    version: "",
    vendorId: 7531,
    productId: 2,
    clazz: 9,
    subClass: 0,
    protocol: 1,
    devAddress: 1,
    busNum: 1,
    configs: [
      {
        id: 1,
        attributes: 224,
        isRemoteWakeup: true,
        isSelfPowered: true,
        maxPower: 0,
        name: "1-1",
        interfaces: [
          {
            id: 0,
            protocol: 0,
            clazz: 9,
            subClass: 0,
            alternateSetting: 0,
            name: "1-1",
            endpoints: [
              {
                address: 129,
                attributes: 3,
                interval: 12,
                maxPacketSize: 4,
                direction: 128,
                number: 1,
                type: 3,
                interfaceId: 0,
              },
            ],
          },
        ],
      },
    ],
  },
]
*/

usbManager.connectDevice

connectDevice(device: USBDevice): Readonly&lt;USBDevicePipe&gt;

Connects to the USB device based on the device information returned by getDevices(). If the USB service is abnormal, undefined may be returned. Check whether the return value of the API is empty.

  1. Call usbManager.getDevices to obtain the USB device list.
  2. Call usbManager.requestRight to request the permission to use the device.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
device USBDevice Yes USB device. The busNum and devAddress parameters obtained by getDevices are used to determine a USB device. Other parameters are passed transparently.

Return value

Type Description
Readonly&lt;USBDevicePipe&gt; USB device pipe for data transfer.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.
14400001 Access right denied. Call requestRight to get the USBDevicePipe access right first.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
console.log(`devicepipe = ${devicepipe}`);

usbManager.hasRight

hasRight(deviceName: string): boolean

Checks whether the application has the permission to access the device.

Checks whether the user, for example, the application or system, has the device access permissions. The value true is returned if the user has the device access permissions; the value false is returned otherwise.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
deviceName string Yes Device name, which can be obtained from the device list returned by getDevices.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
boolean Returns true if the application has the permission to access the device; returns false otherwise. If this API fails to be called, the following error codes are returned:
- 88080385: This API is not initialized.
- 88080492: An error occurs when the service data packet is written.
- 88080493: An error occurs when the service data packet is read.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let right: boolean = usbManager.hasRight(device.name);
console.log(`${right}`);

usbManager.requestRight

requestRight(deviceName: string): Promise&lt;boolean&gt;

Requests the temporary device access permission for the application. This API uses a promise to return the result. System applications are granted the device access permission by default, and you do not need to apply for the permission separately.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
deviceName string Yes Device name, which can be obtained from the device list returned by getDevices.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
Promise&lt;boolean&gt; Promise used to return the result. The value true indicates that the temporary device access permissions are granted; and the value false indicates the opposite. If this API fails to be called, the following error codes are returned:
- 88080385: This API is not initialized.
- 88080392: An error occurs when the API data packet is written.
- 88080393: An error occurs when the API data packet is read.
- 88080492: An error occurs when the service data packet is written.
- 88080493: An error occurs when the service data packet is read.
- 88080497: An error occurs when the internal logic of the service is executed.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name).then(ret => {
  console.log(`requestRight = ${ret}`);
});

usbManager.removeRight

removeRight(deviceName: string): boolean

Removes the device access permission for the application. System applications are granted the device access permission by default, and calling this API will not revoke the permission.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
deviceName string Yes Device name, which can be obtained from the device list returned by getDevices.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
boolean Permission removal result. The value true indicates that the access permission is removed successfully; and the value false indicates the opposite. If this API fails to be called, the following error codes are returned:
- 88080382: An invalid value or parameter occurs during the API operation.
- 88080385: This API is not initialized.
- 88080392: An error occurs when the API data packet is written.
- 88080393: An error occurs when the API data packet is read.
- 88080492: An error occurs when the service data packet is written.
- 88080493: An error occurs when the service data packet is read.
- 88080497: An error occurs when the internal logic of the service is executed.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

let device: usbManager.USBDevice = devicesList[0];
if (usbManager.removeRight(device.name)) {
  console.log(`Succeed in removing right`);
}

usbManager.claimInterface

claimInterface(pipe: USBDevicePipe, iface: USBInterface, force ?: boolean): number

Claims a USB interface.

  1. Call usbManager.getDevices to obtain the USB device list and interfaces.
  2. Call usbManager.requestRight to request the device access permission.
  3. Call usbManager.connectDevice to obtain devicepipe as an input parameter.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
pipe USBDevicePipe Yes USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value.
iface USBInterface Yes USB interface. You can use getDevices to obtain device information and identify the USB interface based on its ID.
force boolean No Whether to forcibly claim a USB interface. The default value is false, which means not to forcibly claim a USB interface. You can set the value as required.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
number Returns 0 if the USB interface is successfully claimed; returns an error code otherwise. The error codes are as follows:
- 63: The data exceeds the expected maximum volume.
- 88080385: This API is not initialized.
- 88080482: An invalid value or parameter occurs during the service.
- 88080484: No permission.
- 88080492: An error occurs when the service data packet is written.
- 88080493: An error occurs when the service data packet is read.
- 88080497: An error occurs when the internal logic of the service is executed.
- -1: The underlying interface fails to be called.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
let interfaces: usbManager.USBInterface = device.configs[0].interfaces[0];
let ret: number= usbManager.claimInterface(devicepipe, interfaces);
console.log(`claimInterface = ${ret}`);

usbManager.releaseInterface

releaseInterface(pipe: USBDevicePipe, iface: USBInterface): number

Releases a USB interface.

Before you do this, ensure that you have claimed the interface by calling usbManager.claimInterface.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
pipe USBDevicePipe Yes USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value.
iface USBInterface Yes USB interface. You can use getDevices to obtain device information and identify the USB interface based on its ID.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error.Possible causes:1.Mandatory parameters are left unspecified.2.Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
number Returns 0 if the USB interface is successfully released; returns an error code otherwise. The error codes are as follows:
- 63: The data exceeds the expected maximum volume.
- 88080381: Invalid interface operation.
- 88080385: This API is not initialized.
- 88080482: An invalid value or parameter occurs during the service.
- 88080484: No permission.
- 88080492: An error occurs when the service data packet is written.
- 88080493: An error occurs when the service data packet is read.
- 88080497: An error occurs when the internal logic of the service is executed.
- -1: The underlying interface fails to be called.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
let interfaces: usbManager.USBInterface = device.configs[0].interfaces[0];
let ret: number = usbManager.claimInterface(devicepipe, interfaces);
ret = usbManager.releaseInterface(devicepipe, interfaces);
console.log(`releaseInterface = ${ret}`);

usbManager.setConfiguration

setConfiguration(pipe: USBDevicePipe, config: USBConfiguration): number

Sets the device configuration.

  1. Call usbManager.getDevices to obtain the USB device list and device configuration.
  2. Call usbManager.requestRight to request the device access permission.
  3. Call usbManager.connectDevice to obtain devicepipe as an input parameter.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
pipe USBDevicePipe Yes USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value.
config USBConfiguration Yes USB configuration. You can use getDevices to obtain device information and identify the USB configuration based on the ID.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
number Returns 0 if the USB configuration is successfully set; returns an error code otherwise. The error codes are as follows:
- 63: The data exceeds the expected maximum volume.
- 88080385: This API is not initialized.
- 88080482: An invalid value or parameter occurs during the service.
- 88080484: No permission.
- 88080492: An error occurs when the service data packet is written.
- 88080493: An error occurs when the service data packet is read.
- 88080497: An error occurs when the internal logic of the service is executed.
- -1: The underlying interface fails to be called.
- -17: I/O failure.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
let config: usbManager.USBConfiguration = device.configs[0];
let ret: number= usbManager.setConfiguration(devicepipe, config);
console.log(`setConfiguration = ${ret}`);

usbManager.setInterface

setInterface(pipe: USBDevicePipe, iface: USBInterface): number

Sets a USB interface.

  1. Call usbManager.getDevices to obtain the device list and interfaces.
  2. Call usbManager.requestRight to request the device access permission.
  3. Call usbManager.connectDevice to obtain devicepipe as an input parameter.
  4. Call usbManager.claimInterface to register a communication interface.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
pipe USBDevicePipe Yes USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value.
iface USBInterface Yes USB interface. You can use getDevices to obtain device information and identify the USB interface based on its id and alternateSetting.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
number Returns 0 if the USB interface is successfully set; returns an error code otherwise. The error codes are as follows:
- 63: The data exceeds the expected maximum volume.
- 88080385: This API is not initialized.
- 88080482: An invalid value or parameter occurs during the service.
- 88080484: No permission.
- 88080492: An error occurs when the service data packet is written.
- 88080493: An error occurs when the service data packet is read.
- 88080497: An error occurs when the internal logic of the service is executed.
- -1: The underlying interface fails to be called.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
let interfaces: usbManager.USBInterface = device.configs[0].interfaces[0];
let ret: number = usbManager.claimInterface(devicepipe, interfaces);
ret = usbManager.setInterface(devicepipe, interfaces);
console.log(`setInterface = ${ret}`);

usbManager.getRawDescriptor

getRawDescriptor(pipe: USBDevicePipe): Uint8Array

Obtains the raw USB descriptor. If the USB service is abnormal, undefined may be returned. Check whether the return value of the API is empty.

  1. Call usbManager.getDevices to obtain the USB device list.
  2. Call usbManager.requestRight to request the device access permission.
  3. Call usbManager.connectDevice to obtain devicepipe as an input parameter.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
pipe USBDevicePipe Yes USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
Uint8Array Returns the raw USB descriptor if the operation is successful; returns undefined otherwise.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

usbManager.requestRight(devicesList[0].name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(devicesList[0]);
let ret: Uint8Array = usbManager.getRawDescriptor(devicepipe);

usbManager.getFileDescriptor

getFileDescriptor(pipe: USBDevicePipe): number

Obtains the file descriptor.

  1. Call usbManager.getDevices to obtain the USB device list.
  2. Call usbManager.requestRight to request the device access permission.
  3. Call usbManager.connectDevice to obtain devicepipe as an input parameter.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
pipe USBDevicePipe Yes USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
number Returns the file descriptor corresponding to the device if this API is successful called; returns an error code otherwise. The error codes are as follows:
- 63: The data exceeds the expected maximum volume.
- 88080385: This API is not initialized.
- 88080482: An invalid value or parameter occurs during the service.
- 88080484: No permission.
- 88080492: An error occurs when the service data packet is written.
- 88080493: An error occurs when the service data packet is read.
- 88080497: An error occurs when the internal logic of the service is executed.
- -1: The underlying interface fails to be called.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

usbManager.requestRight(devicesList[0].name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(devicesList[0]);
let ret: number = usbManager.getFileDescriptor(devicepipe);

usbManager.controlTransfer(deprecated)

controlTransfer(pipe: USBDevicePipe, controlparam: USBControlParams, timeout ?: number): Promise&lt;number&gt;

Performs control transfer.

  1. Call usbManager.getDevices to obtain the USB device list.
  2. Call usbManager.requestRight to request the device access permission.
  3. Call usbManager.connectDevice to obtain devicepipe as an input parameter.

NOTE

This API is supported since API version 9 and deprecated since API version 12. You are advised to use usbControlTransfer.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
pipe USBDevicePipe Yes USB device pipe. You need to call connectDevice to obtain its value.
controlparam USBControlParams Yes Control transfer parameters. Set the parameters as required. For details, see the USB protocol.
timeout number No (Optional) Timeout duration, in ms. The default value is 0. You can set this parameter as required.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.

Return value

Type Description
Promise&lt;number&gt; Promise used to return the result, which is the size of the transferred or received data block if the transfer is successful. If the API call fails, the following error codes are returned:
- 88080385: This API is not initialized.
- 88080482: An invalid value or parameter occurs during the service.
- 88080484: No permission.
- 88080492: An error occurs when the service data packet is written.
- 88080493: An error occurs when the service data packet is read.
- 88080497: An error occurs when the internal logic of the service is executed.
- -1: The underlying interface fails to be called.

Example

class PARA {
  request: number = 0
  reqType: usbManager.USBControlRequestType = 0
  target: usbManager.USBRequestTargetType = 0
  value: number = 0
  index: number = 0
  data: Uint8Array = new Uint8Array()
}

let param: PARA = {
  request: 0x06,
  reqType: 0x80,
  target:0,
  value: 0x01 << 8|0,
  index: 0,
  data: new Uint8Array(18)
};

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

usbManager.requestRight(devicesList[0].name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(devicesList[0]);
usbManager.controlTransfer(devicepipe, param).then((ret: number) => {
console.log(`controlTransfer = ${ret}`);
})

usbManager.usbControlTransfer12+

usbControlTransfer(pipe: USBDevicePipe, requestparam: USBDeviceRequestParams, timeout ?: number): Promise&lt;number&gt;

Performs control transfer.

  1. Call usbManager.getDevices to obtain the USB device list.
  2. Call usbManager.requestRight to request the device access permission.
  3. Call usbManager.connectDevice to obtain devicepipe as an input parameter.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
pipe USBDevicePipe Yes USB device pipe, which is used to determine the USB device.
requestparam USBDeviceRequestParams Yes Control transfer parameters. Set the parameters as required. For details, see the USB protocol.
timeout number No (Optional) Timeout duration, in ms. The default value is 0, indicating no timeout.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error.Possible causes:1.Mandatory parameters are left unspecified.2.Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
Promise&lt;number&gt; Promise used to return the result, which is the size of the transferred or received data block if the transfer is successful. If the API call fails, the following error codes are returned:
- 88080385: This API is not initialized.
- 88080482: An invalid value or parameter occurs during the service.
- 88080484: No permission.
- 88080492: An error occurs when the service data packet is written.
- 88080493: An error occurs when the service data packet is read.
- 88080497: An error occurs when the internal logic of the service is executed.
- -1: The underlying interface fails to be called.

Example

class PARA {
  bmRequestType: number = 0
  bRequest: number = 0
  wValue: number = 0
  wIndex: number = 0
  wLength: number = 0
  data: Uint8Array = new Uint8Array()
}

let param: PARA = {
  bmRequestType: 0x80,
  bRequest: 0x06,

  wValue:0x01 << 8|0,
  wIndex: 0,
  wLength: 18,
  data: new Uint8Array(18)
};

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

usbManager.requestRight(devicesList[0].name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(devicesList[0]);
usbManager.usbControlTransfer(devicepipe, param).then((ret: number) => {
console.log(`usbControlTransfer = ${ret}`);
})

usbManager.bulkTransfer

bulkTransfer(pipe: USBDevicePipe, endpoint: USBEndpoint, buffer: Uint8Array, timeout ?: number): Promise&lt;number&gt;

Performs bulk transfer.

  1. Call usbManager.getDevices to obtain the USB device list and endpoints.
  2. Call usbManager.requestRight to request the device access permission.
  3. Call usbManager.connectDevice to obtain the returned devicepipe.
  4. Obtain the usbManager.claimInterface API.
  5. Call the usbManager.bulkTransfer API.

NOTE

The total amount of data (including pipe, endpoint, buffer, and timeout) transferred in bulk must be less than 200 KB.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
pipe USBDevicePipe Yes USB device pipe. You need to call connectDevice to obtain its value.
endpoint USBEndpoint Yes USB endpoint, which is used to determine the USB interface for data transfer. You need to call getDevices to obtain the device information list and endpoint. Wherein, address is used to determine the endpoint address, direction is used to determine the endpoint direction, and interfaceId is used to determine the USB interface to which the endpoint belongs. Other parameters are passed transparently.
buffer Uint8Array Yes Buffer used to write or read data.
timeout number No (Optional) Timeout duration, in ms. The default value is 0. You can set this parameter as required.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
Promise&lt;number&gt; Promise used to return the result, which is the size of the transferred or received data block if the transfer is successful. If the API call fails, the following error codes are returned:
- 63: The data exceeds the expected maximum volume.
- 88080385: This API is not initialized.
- 88080482: An invalid value or parameter occurs during the service.
- 88080484: No permission.
- 88080492: An error occurs when the service data packet is written.
- 88080493: An error occurs when the service data packet is read.
- 88080497: An error occurs when the internal logic of the service is executed.
- -1: The underlying interface fails to be called.
- -3: The parameter is invalid.
- -202: The device is not found.

Example

NOTE

The following sample code is only a basic process for calling the bulkTransfer API. In actual calling, you must comply with the device-related protocols to ensure correct data transfer and device compatibility.

// Call usbManager.getDevices to obtain a data set. Then, obtain a USB device and its access permission.
// Pass the obtained USB device as a parameter to usbManager.connectDevice. Then, call usbManager.connectDevice to connect the USB device.
// Call usbManager.claimInterface to claim a USB interface. After that, call usbManager.bulkTransfer to start bulk transfer.
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);

let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
for (let i = 0; i < device.configs[0].interfaces.length; i++) {
  if (device.configs[0].interfaces[i].endpoints[0].attributes == 2) {
    let endpoint: usbManager.USBEndpoint = device.configs[0].interfaces[i].endpoints[0];
    let interfaces: usbManager.USBInterface = device.configs[0].interfaces[i];
    let ret: number = usbManager.claimInterface(devicepipe, interfaces);
    let buffer =  new Uint8Array(128);
    usbManager.bulkTransfer(devicepipe, endpoint, buffer).then((ret: number) => {
      console.log(`bulkTransfer = ${ret}`);
    });
  }
}

usbManager.usbSubmitTransfer18+

usbSubmitTransfer(transfer: UsbDataTransferParams): void

Requests a USB data transfer.

This API uses an asynchronous callback to return the result.

  1. Call usbManager.getDevices to obtain the USB device list and endpoints.
  2. Call usbManager.requestRight to request the device access permission.
  3. Call usbManager.connectDevice to obtain the returned devicepipe.
  4. Obtain the usbManager.claimInterface API.
  5. Call the usbManager.usbSubmitTransfer API.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
transfer UsbDataTransferParams Yes As a USB data transfer interface, it is required for a client to initiate a transfer request.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.
801 Capability not supported.
14400001 Access right denied. Call requestRight to get the USBDevicePipe access right first.
14400007 Resource busy.
14400008 No such device (it may have been disconnected).
14400009 Insufficient memory.
14400012 Transmission I/O error.

Example

NOTE

The following sample code shows the basic process for calling the usbSubmitTransfer API and it needs to be executed in a specific method. In actual calling, you must comply with the device-related protocols to ensure correct data transfer and device compatibility.

// Call usbManager.getDevices to obtain a data set. Then, obtain a USB device and its access permission.
// Pass the obtained USB device as a parameter to usbManager.connectDevice. Then, call usbManager.connectDevice to connect the USB device.
// Call usbManager.claimInterface to claim a USB interface. After that, call usbManager.bulkTransfer to start bulk transfer.
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
  return;
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
// Obtain the endpoint address.
let endpoint = device.configs[0].interfaces[0]?.endpoints.find((value) => {
  return value.direction === 0 && value.type === 2
})
// Obtain the first ID of the device.
let ret: number = usbManager.claimInterface(devicepipe, device.configs[0].interfaces[0], true);

let transferParams: usbManager.UsbDataTransferParams = {
  devPipe: devicepipe,
  flags: usbManager.UsbTransferFlags.USB_TRANSFER_SHORT_NOT_OK,
  endpoint: 1,
  type: usbManager.UsbEndpointTransferType.TRANSFER_TYPE_BULK,
  timeout: 2000,
  length: 10, 
  callback: () => {},
  userData: new Uint8Array(10),
  buffer: new Uint8Array(10),
  isoPacketCount: 0,
};
try {
  transferParams.endpoint=endpoint?.address as number;
  transferParams.callback=(err, callBackData: usbManager.SubmitTransferCallback)=>{
    console.info('callBackData =' +JSON.stringify(callBackData));
  }
  usbManager.usbSubmitTransfer(transferParams); 
  console.info('USB transfer request submitted.');
} catch (error) {
  console.error('USB transfer failed:', error);
}

usbManager.usbCancelTransfer18+

usbCancelTransfer(transfer: UsbDataTransferParams): void

Cancels an asynchronous USB data transfer request.

  1. Call usbManager.getDevices to obtain the USB device list and endpoints.
  2. Call usbManager.requestRight to request the device access permission.
  3. Call usbManager.connectDevice to obtain the returned devicepipe.
  4. Obtain the usbManager.claimInterface API.
  5. Call the usbManager.usbCancelTransfer API.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
transfer UsbDataTransferParams Yes Only USBDevicePipe and endpoint are required for canceling the transfer.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.
801 Capability not supported.
14400001 Access right denied. Call requestRight to get the USBDevicePipe access right first.
14400008 No such device (it may have been disconnected).
14400010 Other USB error. Possible causes:
1.Unrecognized discard error code.
14400011 The transfer is not in progress, or is already complete or cancelled.

Return value

Type Description
&lt;void&gt; None.

Example

NOTE

The following sample code shows the basic process for calling the usbCancelTransfer API and it needs to be executed in a specific method. In actual calling, you must comply with the device-related protocols to ensure correct data transfer and device compatibility.

// Call usbManager.getDevices to obtain a data set. Then, obtain a USB device and its access permission.
// Pass the obtained USB device as a parameter to usbManager.connectDevice. Then, call usbManager.connectDevice to connect the USB device.
// Call usbManager.claimInterface to claim a USB interface. After that, call usbManager.bulkTransfer to start bulk transfer.
let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
  return;
}
let device: usbManager.USBDevice = devicesList[0];
usbManager.requestRight(device.name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(device);
// Obtain the endpoint address.
let endpoint = device.configs[0].interfaces[0]?.endpoints.find((value) => {
  return value.direction === 0 && value.type === 2
})
// Obtain the first ID of the device.
let ret: number = usbManager.claimInterface(devicepipe, device.configs[0].interfaces[0], true);
let transferParams: usbManager.UsbDataTransferParams = {
  devPipe: devicepipe,
  flags: usbManager.UsbTransferFlags.USB_TRANSFER_SHORT_NOT_OK,
  endpoint: 1,
  type: usbManager.UsbEndpointTransferType.TRANSFER_TYPE_BULK,
  timeout: 2000,
  length: 10, 
  callback: () => {},
  userData: new Uint8Array(10),
  buffer: new Uint8Array(10),
  isoPacketCount: 0,
};
try {
  transferParams.endpoint=endpoint?.address as number;
  transferParams.callback=(err, callBackData: usbManager.SubmitTransferCallback)=>{
    console.info('callBackData =' +JSON.stringify(callBackData));
  }
  usbManager.usbSubmitTransfer(transferParams);
  usbManager.usbCancelTransfer(transferParams);
  console.info('USB transfer request submitted.');
} catch (error) {
  console.error('USB transfer failed:', error);
}

usbManager.closePipe

closePipe(pipe: USBDevicePipe): number

Closes a USB device pipe.

  1. Call usbManager.getDevices to obtain the USB device list.
  2. Call usbManager.requestRight to request the device access permission.
  3. Call usbManager.connectDevice to obtain devicepipe as an input parameter.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
pipe USBDevicePipe Yes USB device pipe, which is used to determine the message control channel. You need to call connectDevice to obtain its value.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.

Return value

Type Description
number Returns 0 if the USB device pipe is closed successfully; returns an error code otherwise. The error codes are as follows:
- 63: The data exceeds the expected maximum volume.
- 88080393: An error occurs when the API data packet is read.
- 88080482: An invalid value or parameter occurs during the service.
- 88080484: No permission.
- 88080493: An error occurs when the service data packet is read.
- 88080497: An error occurs when the internal logic of the service is executed.
- -1: The underlying interface fails to be called.

Example

let devicesList: Array<usbManager.USBDevice> = usbManager.getDevices();
if (devicesList.length == 0) {
  console.log(`device list is empty`);
}

usbManager.requestRight(devicesList[0].name);
let devicepipe: usbManager.USBDevicePipe = usbManager.connectDevice(devicesList[0]);
let ret: number = usbManager.closePipe(devicepipe);
console.log(`closePipe = ${ret}`);

usbManager.hasAccessoryRight14+

hasAccessoryRight(accessory: USBAccessory): boolean

Checks whether the application has the permission to access the USB accessory.

You need to call usbManager.getAccessoryList to obtain the accessory list and use USBAccessory as a parameter.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
accessory USBAccessory Yes USB accessory.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.
14400004 Service exception. Possible causes: 1. No accessory is plugged in.
14400005 Database operation exception.
14401001 The target USBAccessory not matched.

Return value

Type Description
boolean The value true indicates that the application has the permission to access the USB accessory; false indicates the opposite.

Example

import { hilog } from '@kit.PerformanceAnalysisKit';
try {
  let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
  let flag = usbManager.hasAccessoryRight(accList[0])
  hilog.info(0, 'testTag ui', `hasAccessoryRight success, ret:${flag}`)
} catch (error) {
  hilog.info(0, 'testTag ui', `hasAccessoryRight error ${error.code}, message is ${error.message}`)
}

usbManager.requestAccessoryRight14+

requestAccessoryRight(accessory: USBAccessory): Promise&lt;boolean&gt;

Requests the permission to access a USB accessory for a specified application.

You need to call usbManager.getAccessoryList to obtain the accessory list and use USBAccessory as a parameter.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
accessory USBAccessory Yes USB accessory.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.
14400004 Service exception. Possible causes: 1. No accessory is plugged in.
14400005 Database operation exception.
14401001 The target USBAccessory not matched.

Return value

Type Description
Promise&lt;boolean&gt; Promise used to return the application result. The value true indicates that the device access permissions are granted; false indicates the opposite.

Example

import { hilog } from '@kit.PerformanceAnalysisKit';
try {
  let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
  let flag = usbManager.requestAccessoryRight(accList[0])
  hilog.info(0, 'testTag ui', `requestAccessoryRight success, ret:${flag}`)
} catch (error) {
  hilog.info(0, 'testTag ui', `requestAccessoryRight error ${error.code}, message is ${error.message}`)
}

usbManager.cancelAccessoryRight14+

cancelAccessoryRight(accessory: USBAccessory): void

Cancels the permission of the current application to access USB accessories.

You need to call usbManager.getAccessoryList to obtain the accessory list and use USBAccessory as a parameter.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
accessory USBAccessory Yes USB accessory.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.
14400004 Service exception. Possible causes: 1. No accessory is plugged in.
14400005 Database operation exception.
14401001 The target USBAccessory not matched.

Example

import { hilog } from '@kit.PerformanceAnalysisKit';
try {
  let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
  let flag = usbManager.requestAccessoryRight(accList[0])
  usbManager.cancelAccessoryRight(accList[0])
  hilog.info(0, 'testTag ui', `cancelAccessoryRight success`)
} catch (error) {
  hilog.info(0, 'testTag ui', `cancelAccessoryRight error ${error.code}, message is ${error.message}`)
}

usbManager.getAccessoryList14+

getAccessoryList(): Array

Obtains the list of USB accessories connected to the host.

System capability: SystemCapability.USB.USBManager

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
801 Capability not supported.
14400004 Service exception. Possible causes: 1. No accessory is plugged in.

Return value

Type Description
Array List of USB accessories (read-only). Currently, only one USB accessory is contained in the list.

Example

import { hilog } from '@kit.PerformanceAnalysisKit';
try {
  let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
  hilog.info(0, 'testTag ui', `getAccessoryList success, accList: ${JSON.stringify(accList)}`)
} catch (error) {
  hilog.info(0, 'testTag ui', `getAccessoryList error ${error.code}, message is ${error.message}`)
}

usbManager.openAccessory14+

openAccessory(accessory: USBAccessory): USBAccessoryHandle

Obtains the accessory handle and opens the accessory file descriptor.

You need to call usbManager.getAccessoryList to obtain the accessory list and use USBAccessory as a parameter.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
accessory USBAccessory Yes USB accessory.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.
14400001 Permission denied. Call requestAccessoryRight to get the right first.
14400004 Service exception. Possible causes: 1. No accessory is plugged in.
14401001 The target USBAccessory not matched.
14401002 Failed to open the native accessory node.
14401003 Cannot reopen the accessory.

Return value

Type Description
USBAccessoryHandle USB accessory handle.

Example

import { hilog } from '@kit.PerformanceAnalysisKit';
try {
  let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
  let flag = usbManager.requestAccessoryRight(accList[0])
  let handle = usbManager.openAccessory(accList[0])
  hilog.info(0, 'testTag ui', `openAccessory success`)
} catch (error) {
  hilog.info(0, 'testTag ui', `openAccessory error ${error.code}, message is ${error.message}`)
}

usbManager.closeAccessory14+

closeAccessory(accessoryHandle: USBAccessoryHandle): void

Closes the accessory file descriptor.

You need to call usbManager.openAccessory to obtain the accessory list and use USBAccessoryHandle as a parameter.

System capability: SystemCapability.USB.USBManager

Parameters

Name Type Mandatory Description
accessoryHandle USBAccessoryHandle Yes USB accessory handle, obtained through openAccessory.

Error codes

For details about the error codes, see USB Service Error Codes.

ID Error Message
401 Parameter error. Possible causes: 1. Mandatory parameters are left unspecified. 2. Incorrect parameter types.
801 Capability not supported.
14400004 Service exception. Possible causes: 1. No accessory is plugged in.

Example

import { hilog } from '@kit.PerformanceAnalysisKit';
try {
  let accList: usbManager.USBAccessory[] = usbManager.getAccessoryList()
  let flag = usbManager.requestAccessoryRight(accList[0])
  let handle = usbManager.openAccessory(accList[0])
  usbManager.closeAccessory(handle)
  hilog.info(0, 'testTag ui', `closeAccessory success`)
} catch (error) {
  hilog.info(0, 'testTag ui', `closeAccessory error ${error.code}, message is ${error.message}`)
}

USBEndpoint

Represents the USB endpoint from which data is sent or received. You can obtain the USB endpoint through USBInterface.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
address number Yes Endpoint address.
attributes number Yes Endpoint attributes.
interval number Yes Endpoint interval.
maxPacketSize number Yes Maximum size of data packets on the endpoint.
direction USBRequestDirection Yes Endpoint direction.
number number Yes Endpoint number.
type number Yes Endpoint type.
interfaceId number Yes Unique ID of the interface to which the endpoint belongs.

USBInterface

Represents a USB interface. One USBConfiguration object can contain multiple USBInterface instances, each providing a specific function.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
id number Yes Unique ID of the USB interface.
protocol number Yes Interface protocol.
clazz number Yes Device type.
subClass number Yes Device subclass.
alternateSetting number Yes Settings for alternating between descriptors of the same USB interface.
name string Yes Interface name.
endpoints Array&lt;USBEndpoint&gt; Yes Endpoints that belong to the USB interface.

USBConfiguration

Represents the USB configuration. One USBDevice can contain multiple USBConfig instances.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
id number Yes Unique ID of the USB configuration.
attributes number Yes Configuration attributes.
maxPower number Yes Maximum power consumption, in mA.
name string Yes Configuration name, which can be left empty.
isRemoteWakeup boolean Yes Support for remote wakeup.
isSelfPowered boolean Yes Support for independent power supplies.
interfaces Array&nbsp;&lt;USBInterface&gt; Yes Supported interface attributes.

USBDevice

Represents the USB device information.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
busNum number Yes Bus address.
devAddress number Yes Device address.
serial string Yes Sequence number.
name string Yes Device name.
manufacturerName string Yes Device manufacturer.
productName string Yes Product name.
version string Yes Version number.
vendorId number Yes Vendor ID.
productId number Yes Product ID.
clazz number Yes Device class.
subClass number Yes Device subclass.
protocol number Yes Device protocol code.
configs Array&lt;USBConfiguration&gt; Yes Device configuration descriptor information.

USBDevicePipe

Represents a USB device pipe, which is used to determine a USB device.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
busNum number Yes Bus address.
devAddress number Yes Device address.

USBControlParams(deprecated)

Represents control transfer parameters.

NOTE

This API is supported since API version 9 and deprecated since API version 18. You are advised to use USBDeviceRequestParams instead.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
request number Yes Request type.
target USBRequestTargetType Yes Request target type.
reqType USBControlRequestType Yes Control request type.
value number Yes Request parameter.
index number Yes Index of the request parameter.
data Uint8Array Yes Buffer for writing or reading data.

USBDeviceRequestParams12+

Represents control transfer parameters.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
bmRequestType number Yes Control request type.
bRequest number Yes Request type.
wValue number Yes Request parameter.
wIndex number Yes Index of the request parameter.
wLength number Yes Length of the requested data.
data Uint8Array Yes Buffer for writing or reading data.

USBRequestTargetType

Enumerates request target types.

System capability: SystemCapability.USB.USBManager

Name Value Description
USB_REQUEST_TARGET_DEVICE 0 Device.
USB_REQUEST_TARGET_INTERFACE 1 Interface.
USB_REQUEST_TARGET_ENDPOINT 2 Endpoint.
USB_REQUEST_TARGET_OTHER 3 Other.

USBControlRequestType

Enumerates control request types.

System capability: SystemCapability.USB.USBManager

Name Value Description
USB_REQUEST_TYPE_STANDARD 0 Standard.
USB_REQUEST_TYPE_CLASS 1 Class.
USB_REQUEST_TYPE_VENDOR 2 Vendor.

USBRequestDirection

Enumerates request directions.

System capability: SystemCapability.USB.USBManager

Name Value Description
USB_REQUEST_DIR_TO_DEVICE 0 Request for writing data from the host to the device.
USB_REQUEST_DIR_FROM_DEVICE 0x80 Request for reading data from the device to the host.

USBAccessory14+

Describes the USB accessory information.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
manufacturer string Yes Manufacturer of an accessory.
product string Yes Product type of an accessory.
description string Yes Description of an accessory.
version string Yes Version of an accessory.
serialNumber string Yes SN of an accessory.

USBAccessoryHandle14+

Describes the USB accessory handle.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
accessoryFd number Yes Accessory file descriptor. A valid accessoryFd is a positive integer.

UsbDataTransferParams18+

As a USB data transfer interface, it is required for a client to initiate a transfer request.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
devPipe USBDevicePipe Yes USB device pipe, which is used to determine the bus number and device address. You need to call connectDevice to obtain its value.
flags UsbTransferFlags Yes USB transfer flag.
endpoint number Yes Endpoint address, which is a positive integer.
type UsbEndpointTransferType Yes Transfer type.
timeout number Yes Timeout duration, in ms.
length number Yes Length of the data buffer, in bytes. The value must be a non-negative number (expected length).
callback AsyncCallback<SubmitTransferCallback> Yes Information returned by the callback.
userData Uint8Array Yes User data.
buffer Uint8Array Yes Buffer, which is used to store data for read or write requests.
isoPacketCount number Yes Number of data packets during real-time transfer, used only for I/Os with real-time transfer endpoints. The value must be a non-negative number.

UsbTransferFlags18+

Enumerates USB transfer flags.

System capability: SystemCapability.USB.USBManager

Name Value Description
USB_TRANSFER_SHORT_NOT_OK 0 Reports short frames as errors.
USB_TRANSFER_FREE_BUFFER 1 Automatically releases the transfer buffer.
USB_TRANSFER_FREE_TRANSFER 2 Automatically transfers after the callback is complete.
USB_TRANSFER_ADD_ZERO_PACKET 3 Adds an additional data packet to the transfer.

UsbEndpointTransferType18+

Enumerates USB transfer types.

System capability: SystemCapability.USB.USBManager

Name Value Description
TRANSFER_TYPE_ISOCHRONOUS 0x1 Real-time transfer.
TRANSFER_TYPE_BULK 0x2 Performs bulk transfer.
TRANSFER_TYPE_INTERRUPT 0x3 Interrupt transfer.

SubmitTransferCallback18+

Transfers USB data packets in an asynchronous manner.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
actualLength number Yes Actual length of the read or written data, in bytes.
status UsbTransferStatus Yes Status after reading or writing is complete.
isoPacketDescs Array> Yes Packet information transferred in real time.

UsbTransferStatus18+

Enumerates the statuses returned by libusb through callback after the actual processing is complete.

System capability: SystemCapability.USB.USBManager

Name Value Description
TRANSFER_COMPLETED 0 Transfer completed.
TRANSFER_ERROR 1 Transfer failed.
TRANSFER_TIMED_OUT 2 Transfer timeout.
TRANSFER_CANCELED 3 Transfer canceled.
TRANSFER_STALL 4 Transfer stalled (at bulk/interrupt endpoint).
TRANSFER_NO_DEVICE 5 Device disconnected.
TRANSFER_OVERFLOW 6 Data overflow.

UsbIsoPacketDescriptor18+

Describes packet information returned in real time by the transfer callback.

System capability: SystemCapability.USB.USBManager

Name Type Mandatory Description
length number Yes Expected length of the read or written data, in bytes.
actualLength number Yes Actual length of the read or written data, in bytes.
status UsbTransferStatus Yes Status returned by callback.

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