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# System

Perform low-level file operations using type-safe APIs.

## Topics

### Adopting System

[Adopting Swift File Operations](/documentation/System/adopting-file-operations)

Migrate existing C code to Swift, using the file operations provided by the System module.

[Adopting Swift File Options](/documentation/System/adopting-file-options)

Migrate existing C code to Swift, using the file-operation options provided by the System module.

[Adopting Swift Error Constants](/documentation/System/adopting-errno)

Migrate existing C code to Swift, using the error constants provided by the System module.

### Files

[`FileDescriptor`](/documentation/System/FileDescriptor)

[`FilePath`](/documentation/System/FilePath)

[`FilePermissions`](/documentation/System/FilePermissions)

### Errors

[`Errno`](/documentation/System/Errno)


---

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