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  "title" : "Application, Host, and User Keys"
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# Application, Host, and User Keys

Keys used to specify the common preference domains.

## Discussion

Not all combinations of application, host, and user are supported preference domains. Specifically, `kCFPreferencesAnyHost` is not supported in any combination with other options.

## Topics

### Constants

[`let kCFPreferencesAnyApplication: CFString`](/documentation/CoreFoundation/kCFPreferencesAnyApplication)

Indicates a preference that applies to any application.

[`let kCFPreferencesAnyHost: CFString`](/documentation/CoreFoundation/kCFPreferencesAnyHost)

Indicates a preference that applies to any host.

[`let kCFPreferencesAnyUser: CFString`](/documentation/CoreFoundation/kCFPreferencesAnyUser)

Indicates a preference that applies to any user.

[`let kCFPreferencesCurrentApplication: CFString`](/documentation/CoreFoundation/kCFPreferencesCurrentApplication)

Indicates a preference that applies only to the current application.

[`let kCFPreferencesCurrentHost: CFString`](/documentation/CoreFoundation/kCFPreferencesCurrentHost)

Indicates a preference that applies only to the current host.

[`let kCFPreferencesCurrentUser: CFString`](/documentation/CoreFoundation/kCFPreferencesCurrentUser)

Indicates a preference that applies only to the current user.


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