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# synchronize()

Waits for any pending asynchronous updates to the defaults database and returns; this method is unnecessary and shouldn’t be used.

```
func synchronize() -> Bool
```

## Return Value

<doc://com.apple.documentation/documentation/Swift/true> if the data was saved successfully to disk, otherwise <doc://com.apple.documentation/documentation/Swift/false>.

## See Also

[`removePersistentDomain(forName:)`](/documentation/Foundation/UserDefaults/removePersistentDomain(forName:))

Removes the keys and values from the specified persistent domain.

[`persistentDomain(forName:)`](/documentation/Foundation/UserDefaults/persistentDomain(forName:))

Retrieves the settings from the specified persistent domain.

[`setPersistentDomain(_:forName:)`](/documentation/Foundation/UserDefaults/setPersistentDomain(_:forName:))

Replaces the keys and values in the specified domain with the new keys and values you supply.


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