UIDevice+SystemBuild.swift

extension UIDevice {
    func systemVersion() -> String {
        let os = switch self.userInterfaceIdiom {
        case .pad: "iPadOS"
        case .mac: "Mac Catalyst"
        case .tv: "tvOS"
        case .vision: "visionOS"
        default: "iOS"
        }
        let version = "\(os) \(self.systemVersion)"

        var name = [CTL_KERN, KERN_OSVERSION]
        var length = 0
        guard sysctl(&name, 2, nil, &length, nil, 0) == 0, length > 0 else { return version }
        var build = [CChar](repeating: 0x00, count: length)
        guard sysctl(&name, 2, &build, &length, nil, 0) == 0, length > 0 else { return version }
        return "\(version) (\(String(cString: build)))"
    }
}