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# mach_absolute_time

Returns current value of a clock that increments monotonically in tick units (starting at an arbitrary point), this clock does not increment while the system is asleep.

```
uint64_t mach_absolute_time();
```

## Return Value

		Value of mach absolute time clock.

## Discussion

Prefer to use the equivalent clock_gettime_nsec_np(CLOCK_UPTIME_RAW) in nanoseconds.

> Important:
> This API has the potential of being misused to access device signals to try to identify the device or user, also known as fingerprinting. Regardless of whether a user gives your app permission to track, fingerprinting is not allowed. When you use this API in your app or third-party SDK (an SDK not provided by Apple), declare your usage and the reason for using the API in your app or third-party SDK’s `PrivacyInfo.xcprivacy` file. For more information, including the list of valid reasons for using the API, see <doc://com.apple.documentation/documentation/BundleResources/describing-use-of-required-reason-api>.

---

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