# FFDeviceEscape(_:_:) Sends a hardware-specific command to the device. ``` func FFDeviceEscape(_ deviceReference: FFDeviceObjectReference!, _ pFFEffectEscape: UnsafeMutablePointer!) -> HRESULT ``` ## Parameters `deviceReference` An opaque reference handle to a device object. This is obtained from a previous call to FFCreateDevice. `pFFEffectEscape` Pointer to FFEFFESCAPE structure that describes the command to be sent. On success, the cbOutBuffer member contains the number of bytes of the output buffer used. ## Return Value If the method succeeds, the return value is FF_OK. If the method fails, the return value can be one of the following error values: ## Discussion FFERR_INVALIDPARAM FFERR_UNSUPPORTED ## Discussion Because each driver implements different escapes, it is the application’s responsibility to ensure that it is sending the escape to the correct driver. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)