---
title: UserSendCDB
framework: scsiperipheralsdriverkit
role: symbol
role_heading: Instance Method
platforms: [driverkit 22.0+]
path: scsiperipheralsdriverkit/iouserscsiperipheraldevicetype05/usersendcdb
---

# UserSendCDB

Sends a vendor-specific Command Descriptor Block (CDB) to the device.

## Declaration

```occ
virtual kern_return_t UserSendCDB(SCSIType05OutParameters command, SCSIType05InParameters *response);
```

## Parameters

- `command`: A doc://com.apple.scsiperipheralsdriverkit/documentation/SCSIPeripheralsDriverKit/SCSIType05OutParameters instance that contains the request information.
- `response`: A pointer to a doc://com.apple.scsiperipheralsdriverkit/documentation/SCSIPeripheralsDriverKit/SCSIType05InParameters instance. On return, the framework fills this object with the response data.

## Return Value

Return Value A value that indicates the result of sending the CDB. kIOReturnSuccess indicates success. For error definitions, see IOKit Constants.

## Discussion

Discussion Call this method to deliver vendor-specific 16-byte commands to the external drive that this dext matches.

## See Also

### Sending commands to the device

- [SCSIType05OutParameters](scsiperipheralsdriverkit/scsitype05outparameters.md)
- [SCSIType05OutVersion](scsiperipheralsdriverkit/scsitype05outversion.md)
- [SCSIType05InParameters](scsiperipheralsdriverkit/scsitype05inparameters.md)
- [SCSIType05InVersion](scsiperipheralsdriverkit/scsitype05inversion.md)