---
title: _OSCollectionFlags
framework: kernel
role: pseudoSymbol
path: kernel/oscollection/oscollectionflags
---

# _OSCollectionFlags

## Declaration

```occ
typedef enum {
   kImmutable = 0x00000001,
   kSort = 0x00000002,
   kMASK = (
   unsigned) -1
} _OSCollectionFlags;
```

## Overview

Overview Used with setOptions to indicate the collection's contents should or should not change. An IORegistryEntry object marks collections immutable when set as properties of a registry entry that's attached to a plane. This is generally an advisory flag, used for debugging; setting it does not mean a collection will in fact disallow modifications.

## Topics

### Constants

- [kImmutable](kernel/oscollection/oscollectionflags/kimmutable.md)