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# CFBitVectorCreateCopy(_:_:)

Creates an immutable bit vector that is a copy of another bit vector.

```
func CFBitVectorCreateCopy(_ allocator: CFAllocator!, _ bv: CFBitVector!) -> CFBitVector!
```

## Parameters

`allocator`

The allocator to use to allocate memory for the new bit vector. Pass `NULL` or kCFAllocatorDefault to use the current default allocator.

`bv`

The bit vector to copy.

## Return Value

A new bit vector holding the same bit values as `bv`. Ownership follows the [The Create Rule](https://developer.apple.com/library/archive/documentation/CoreFoundation/Conceptual/CFMemoryMgmt/Concepts/Ownership.html#//apple_ref/doc/uid/20001148-103029).

## Discussion

---

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