Returns the radius of the caption window’s corners.


func MACaptionAppearanceGetWindowRoundedCornerRadius(_ 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 system setting for the caption window’s corner radius.


The rounded corners of the caption window are not customizable within the Accessibility preferences and do not change based on text size.

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