Callback function used to create the value objects stored and returned by a query.
- macOS 10.4+
- Mac Catalyst 13.0+
- Core Services
The query instance.
The attribute name of the value.
The default value of the value.
The user-defined context parameter provided in the
Set Create Value Function
The function must return a pointer-sized value that can be managed with the callback which were set at the same time the create function was given to the query. The value must be returned with a reference (such as if the retain callback had been called on it), as implied by the Create name. If this function doesn't wish to create a new object, it can return the given CFTypeRef, but must also return it with a new retain, and the callbacks must be able to handle a
CFType as an input value.
The function may hold onto the given attribute name and/or value in some other data structure, but must retain them for them to remain valid