\brief The version number in which this entity was deprecated (but is still available).
\brief The version number in which this entity was introduced.
\brief An optional message to provide to a user of this API, e.g., to suggest replacement APIs.
\brief The version number in which this entity was obsoleted, and therefore is no longer available.
\brief A string that describes the platform for which this structure provides availability information.
\brief Whether the entity is unconditionally unavailable on this platform.
Describes the availability of a given entity on a particular platform, e.g., a particular class might only be available on Mac OS 10.7 or newer.