Описание тега cfdata

CFData and its derived mutable type, CFMutableData Reference, provide support for data objects, object-oriented wrappers for byte buffers. Data objects let simple allocated buffers (that is, data with no embedded pointers) take on the behavior of Core Foundation objects. CFData creates static data objects, and CFMutableData creates dynamic data objects. Data objects are typically used for raw data storage.

You use the CFDataCreate and CFDataCreateCopy functions to create static data objects. These functions make a new copy of the supplied data. To create a data object that uses the supplied buffer instead of making a separate copy, use the CFDataCreateWithBytesNoCopy function. You use the CFDataGetBytes function to retrieve the bytes and the CFDataGetLength function to get the length of the bytes.

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