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# CMClockMakeHostTimeFromSystemUnits(_:)

Converts a host time from native units to a core media time structure.

```
func CMClockMakeHostTimeFromSystemUnits(_ hostTime: UInt64) -> CMTime
```

## Parameters

`hostTime`

The host time, in native units, to convert.

## Discussion

The return value has a large integer timescale (for example, nanoseconds). This function handles situations where the host time’s native units use a non-integer timescale.

In macOS, this function converts from the units of `mach_absolute_time`.

---

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