---
title: "CFFileDescriptorIsValid(_:)"
framework: corefoundation
role: symbol
role_heading: Function
path: "corefoundation/cffiledescriptorisvalid(_:)"
---

# CFFileDescriptorIsValid(_:)

Returns a Boolean value that indicates whether the native file descriptor for a given CFFileDescriptor is valid.

## Declaration

```swift
func CFFileDescriptorIsValid(_ f: CFFileDescriptor!) -> Bool
```

## Parameters

- `f`: A CFFileDescriptor.

## Return Value

Return Value true if the native file descriptor for f is valid, otherwise false.

## See Also

### Related Documentation

- [CFFileDescriptorInvalidate(_:)](corefoundation/cffiledescriptorinvalidate(_:).md)

### Getting Information About a File Descriptor

- [CFFileDescriptorGetNativeDescriptor(_:)](corefoundation/cffiledescriptorgetnativedescriptor(_:).md)
- [CFFileDescriptorGetContext(_:_:)](corefoundation/cffiledescriptorgetcontext(_:_:).md)