---
title: "CFSetCreate(_:_:_:_:)"
framework: corefoundation
role: symbol
role_heading: Function
path: "corefoundation/cfsetcreate(_:_:_:_:)"
---

# CFSetCreate(_:_:_:_:)

Creates an immutable CFSet object containing supplied values.

## Declaration

```swift
func CFSetCreate(_ allocator: CFAllocator!, _ values: UnsafeMutablePointer<UnsafeRawPointer?>!, _ numValues: CFIndex, _ callBacks: UnsafePointer<CFSetCallBacks>!) -> CFSet!
```

## Parameters

- `allocator`: The allocator to use to allocate memory for the new set and its storage for values. Pass NULL or doc://com.apple.corefoundation/documentation/CoreFoundation/kCFAllocatorDefault to use the current default allocator.
- `values`: A C array of the pointer-sized values to be in the new set. This parameter may be NULL if the numValues parameter is 0. The C array is not changed or freed by this function. values must be a pointer to a C array of at least numValues elements.
- `numValues`: The number of values to copy from the values C array in the new set.
- `callBacks`: A pointer to a doc://com.apple.corefoundation/documentation/CoreFoundation/CFSetCallBacks structure initialized with the callbacks to use to retain, release, describe, and compare values in the collection. A copy of the contents of the callbacks structure is made, so that a pointer to a structure on the stack can be passed in or can be reused for multiple collection creations. This value may be NULL, which is treated as a valid structure of version 0 with all fields NULL. If the collection contains only CFType objects, then pass doc://com.apple.corefoundation/documentation/CoreFoundation/kCFTypeSetCallBacks to use the default callback functions.

## Return Value

Return Value A new immutable set, or NULL if there was a problem creating the object. Ownership follows the The Create Rule.

## Discussion

Discussion If any value put into the collection is not one understood by one of the callback functions, the behavior when that callback function is used is undefined.

## See Also

### Creating Sets

- [CFSetCreateCopy(_:_:)](corefoundation/cfsetcreatecopy(_:_:).md)