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# CVGetHostClockFrequency()

Returns the frequency of updates to the system time.

```
func CVGetHostClockFrequency() -> Double
```

## Return Value

The current host frequency.

## Discussion

In macOS, the host time bases for Core Video and CoreAudio are identical—both are based on the `mach_absolute_time` function—so the values returned from either API can be used interchangeably.

---

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