---
title: kCFPlugInUnloadFunctionKey
framework: corefoundation
role: symbol
role_heading: Global Variable
path: corefoundation/kcfpluginunloadfunctionkey
---

# kCFPlugInUnloadFunctionKey

Used to specify a plug-in’s unload function.

## Declaration

```swift
let kCFPlugInUnloadFunctionKey: CFString!
```

## See Also

### Constants

- [kCFPlugInDynamicRegistrationKey](corefoundation/kcfplugindynamicregistrationkey.md)
- [kCFPlugInDynamicRegisterFunctionKey](corefoundation/kcfplugindynamicregisterfunctionkey.md)
- [kCFPlugInFactoriesKey](corefoundation/kcfpluginfactorieskey.md)
- [kCFPlugInTypesKey](corefoundation/kcfplugintypeskey.md)