---
title: "SCPreferencesGetSignature(_:)"
framework: systemconfiguration
role: symbol
role_heading: Function
path: "systemconfiguration/scpreferencesgetsignature(_:)"
---

# SCPreferencesGetSignature(_:)

Returns a value that can be used to determine if the saved configuration preferences have changed.

## Declaration

```swift
func SCPreferencesGetSignature(_ prefs: SCPreferences) -> CFData?
```

## Parameters

- `prefs`: The preferences session.

## Return Value

Return Value Data that reflects the signature of the configuration preferences at the time of the call to the SCPreferencesCreate(_:_:_:) function.

## See Also

### Getting Information About a Preferences Session

- [SCPreferencesGetTypeID()](systemconfiguration/scpreferencesgettypeid().md)
- [SCPreferencesCopyKeyList(_:)](systemconfiguration/scpreferencescopykeylist(_:).md)