Returns a preference value for a given domain.
- iOS 2.0+
- macOS 10.0+
- UIKit for Mac 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
- Core Foundation
Preferences key for the value to obtain.
The ID of the application whose preferences are searched. Takes the form of a Java package name, such as
The preference data for the specified domain. If the no value was located, returns
NULL. Ownership follows the The Create Rule.
This function is the primitive get mechanism for the higher level preference function
CFPreferences Unlike the high-level function,
CFPreferences 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.