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# FSUnaryFileSystem

An abstract base class for implementing a minimal file system.

```
class FSUnaryFileSystem
```

## Overview

`FSUnaryFileSystem` is a simplified file system, which works with one [`FSResource`](/documentation/FSKit/FSResource) and presents it as one [`FSVolume`](/documentation/FSKit/FSVolume).

The one volume and its container have a shared state and lifetime, a more constrained life cycle than the [`FSFileSystem`](/documentation/FSKit/FSFileSystem) design flow.

Implement your app extension by providing a subclass of `FSUnaryFileSystem` as a delegate object.
Your delegate also needs to implement the [`FSUnaryFileSystemOperations`](/documentation/FSKit/FSUnaryFileSystemOperations) protocol so that it can load resources.

## Topics

### Implementing operations

[`FSUnaryFileSystemOperations`](/documentation/FSKit/FSUnaryFileSystemOperations)

Operations performed by a unary file system.


---

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