---
title: FSFileSystem
framework: fskit
role: symbol
role_heading: Class
path: fskit/fsfilesystem
---

# FSFileSystem

An abstract base class for implementing a full-featured file system.

## Declaration

```occ
@interface FSFileSystem : NSObject
```

## Overview

Overview FSFileSystem is a full-featured file system, which works with one or more FSResource instances and presents one or more FSVolume references to callers. Implement your app extension by providing a subclass of FSFileSystem as a delegate object. Your delegate also needs to implement the FSFileSystemOperations protocol so that it can probe, load, and unload resources. note: The current version of FSKit supports only FSUnaryFileSystem, not FSFileSystem.

## Relationships

### Inherits From

- [NSObject](objectivec/nsobject-swift.class.md)

### Conforms To

- [FSFileSystemBase](fskit/fsfilesystembase.md)

## See Also

### File systems

- [FSUnaryFileSystem](fskit/fsunaryfilesystem.md)
- [FSFileSystemBase](fskit/fsfilesystembase.md)
- [FSFileName](fskit/fsfilename.md)