# PerformDeviceConfigurationChange Tells the device to handle a configuration change. ``` virtual kern_return_t PerformDeviceConfigurationChange(uint64_t in_change_action, OSObject *in_change_info); ``` ## Parameters `in_change_action` A `uint64_t` that indicates the action the device object takes. This is the same value previously passed to `RequestDeviceConfigurationChange`. This value is purely for the device’s usage; the host doesn’t look at this value. `in_change_info` A pointer to an about the configuration change. This is the same value previously passed to `RequestDeviceConfigurationChange`. This value is purely for the clock device’s usage; the host doesn’t look at this value. Retain and release this object reference as needed. ## Return Value on success, or another value if an error occurs. For a list of error codes, see . ## Discussion The host calls this method to allow the clock device to perform a configuration change. This call can result from a call to `RequestDeviceConfigurationChange` or a from change to an I/O state that requires a configuration change. Subclass and override this method to handle any custom configuration change requests, then call the superclass to update the I/O state. The framework stops I/O prior to performing the configuration change. --- 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)