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# CMTagCollectionCreateMutable

Creates a new, mutable, empty tag collection.

```
extern OSStatus CMTagCollectionCreateMutable(CFAllocatorRef allocator, CFIndex capacity, CMMutableTagCollectionRef*newMutableCollectionOut);
```

## Parameters

`allocator`

The allocator to use for the new tag collection. Pass `kCFAllocatorDefault` to use the default global allocator.

`capacity`

The maximum number of tags the collection can contain. Pass `0` for an unbounded capacity.

`newMutableCollectionOut`

The output destination for the new mutable tag collection.

## Return Value

Returns `0` on success and a value from Tag Collection Error Codes on failure.

---

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