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  "framework" : "FSKit",
  "identifier" : "/documentation/FSKit/FSItem/Identifier",
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  "role" : "Enumeration",
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    "kind" : "Enumeration",
    "modules" : [
      "FSKit"
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  "title" : "FSItem.Identifier"
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-->

# FSItem.Identifier

The unique identifier for an item.

```
enum Identifier
```

## Overview

Use this type when packing items for an enumeration in [`packEntry(name:itemType:itemID:nextCookie:attributes:)`](/documentation/FSKit/FSDirectoryEntryPacker/packEntry(name:itemType:itemID:nextCookie:attributes:)).
Either provide a unique identifier like an inode number, or one of the special enumeration cases this type defines, like [`FSItem.Identifier.rootDirectory`](/documentation/FSKit/FSItem/Identifier/rootDirectory).

## Topics

### Working with special identifiers

[`FSItem.Identifier.invalid`](/documentation/FSKit/FSItem/Identifier/invalid)

The identifier for an invalid item.

[`FSItem.Identifier.parentOfRoot`](/documentation/FSKit/FSItem/Identifier/parentOfRoot)

The identifier for an item that serves as the parent of the root directory.

[`FSItem.Identifier.rootDirectory`](/documentation/FSKit/FSItem/Identifier/rootDirectory)

The item identifier for the root directory.

### Working with raw values

[`init(rawValue:)`](/documentation/FSKit/FSItem/Identifier/init(rawValue:))


---

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