Macos Swift2：初始化不可配置指针的正确方法<；非托管<；CFMutableDictionary>&燃气轮机；要传递给IORegistryEntryCreateCFProperties的参数

好的，在Swift 2中，

IORegistryEntryCreateCFProperties

的定义是

func IORegistryEntryCreateCFProperties(entry: io_registry_entry_t, _ properties: UnsafeMutablePointer<Unmanaged<CFMutableDictionary>?>, _ allocator: CFAllocator!, _ options: IOOptionBits) -> kern_return_t

func IORegistryEntryCreateCFProperties（条目：io\u registry\u entry\u t，\u属性：UnsafeMutablePointer，\u分配器：CFAllocator！，\u选项：IOOptionBits）->kern\u return\t

我能行

var dict: UnsafeMutablePointer<Unmanaged<CFMutableDictionary>?> = nil
kr = IORegistryEntryCreateCFProperties(box as io_registry_entry_t, dict, kCFAllocatorDefault, nilOptions)

var dict:UnsafeMutablePointer=nil
kr=IORegistryEntryCreateCFProperties（框为io\U注册表项、dict、kCFAllocatorDefault、NILPOPTIONS）

---

它编译并运行。当然，它在执行

ioRegistryEntryCreateCProperties

时崩溃，因为

dict

被初始化为

nil

。我的问题是如何将

dict

初始化为非零值？我尝试过各种方法，但都没有成功。

类型的参数

UnsafeMutablePointer<Unmanaged<CFMutableDictionary>?>

Unmanaged<CFMutableDictionary>?

var props : Unmanaged<CFMutableDictionary>?
if IORegistryEntryCreateCFProperties(entry, &props, kCFAllocatorDefault, 0) == KERN_SUCCESS {
    if let props = props {
        let dict = props.takeRetainedValue() as NSDictionary
        print(dict)
    }
}