Returns the preference for font scaling.


func MACaptionAppearanceGetRelativeCharacterSize(_ domain: MACaptionAppearanceDomain, _ behavior: UnsafeMutablePointer<MACaptionAppearanceBehavior>?) -> CGFloat



The domain to retrieve the preference value from. See MACaptionAppearanceDomain. Pass MACaptionAppearanceDomain.user unless the system defaults are needed for comparison.


A pointer to memory. On return, this memory holds the caption appearance behavior for this preference setting. For possible values see MACaptionAppearanceBehavior. Pass NULL when you do not need the behavior setting.

Return Value

The font scaling preference, as a multiplier, for the specified style; ranging from 0.0 to 2.0.

Beta Software

This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.

Learn more about using Apple's beta software