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# SetClockDomain

Sets the clock domain value of the clock device.

```
kern_return_t SetClockDomain(uint32_t in_clock_domain);
```

## Parameters

`in_clock_domain`

The uint32_t clock domain value to set.

## Return Value

A kern_return_t value indicating success or failure.

## Discussion

A uint32_t whose value indicates the clock domain to which the IOUserVideoClockDevice
belongs. IOUserVideoClockDevices that have the same value for this property can
synchronize in hardware. However, a value of 0 indicates that the clock
domain for the device is unspecified; treat it as separate
from every other device’s clock domain, even if they have the value of 0 as
their clock domain as well.

Drivers can change the clock domain of the clock device dynamically. If successful, the clock device sends a notification
to the host to update the object state.

---

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