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# SetMemoryDescriptor

```
virtual kern_return_t SetMemoryDescriptor(IOMemoryDescriptor *memoryDescriptor, uint32_t index);
```

## Parameters

`memoryDescriptor`

The memory descriptor associated with the ring index. Must not be NULL.

`index`

Ring index to be populated

## Return Value

KERN_SUCCESS is successful see IOReturn.h for error codes.

## Discussion\abstract Add a memory descriptor to the ring.
\discussion Caller must fill the ring starting at index 0. The entire ring must be populated up to index size-1

---

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