CFPreferencesCopyValue(_:_:_:_:)
Returns a preference value for a given domain.
Declaration
func CFPreferencesCopyValue(_ key: CFString, _ applicationID: CFString, _ userName: CFString, _ hostName: CFString) -> CFPropertyList?Parameters
- key:
Preferences key for the value to obtain.
- applicationID:
The ID of the application whose preferences are searched. Takes the form of a Java package name, such as
com.foosoft. - userName:
Kcfpreferencescurrentuser if to search the current-user domain, otherwise Kcfpreferencesanyuser to search the any-user domain.
- hostName:
Kcfpreferencescurrenthost if to search the current-host domain, otherwise Kcfpreferencesanyhost to search the any-host domain.
Return Value
The preference data for the specified domain. If the no value was located, returns NULL. Ownership follows the The Create Rule.
Discussion
This function is the primitive get mechanism for the higher level preference function CFPreferencesCopyAppValue(_:_:) Unlike the high-level function, CFPreferencesCopyValue(_:_:_:_:) searches only the exact domain specified. Do not use this function directly unless you have a need. All arguments must be non-NULL. Do not use arbitrary user and host names, instead pass the pre-defined domain qualifier constants.
Note that values returned from this function are immutable, even if you have recently set the value using a mutable object.