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# SCPreferencesSetValue(_:_:_:)

Updates the data associated with the specified preference key with the specified value.

```
func SCPreferencesSetValue(_ prefs: SCPreferences, _ key: CFString, _ value: CFPropertyList) -> Bool
```

## Parameters

`prefs`

The preferences session.

`key`

The preference key.

`value`

The value to associate with the preference key.

## Return Value

`TRUE` if the value was set; `FALSE` if an error occurred.

## Discussion

This function adds or replaces the value associated with the specified key. To commit these changes to permanent storage you must call [`SCPreferencesCommitChanges(_:)`](/documentation/SystemConfiguration/SCPreferencesCommitChanges(_:)).

---

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