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# YieldBuffer

```
virtual kern_return_t YieldBuffer(uint32_t used_len);
```

## Parameters

`used_len`

The length of the buffer used by the client.

## Return Value

0 in case of success. Negative in case of an error.

## Discussion\abstract This function is called to yield the buffer and set the used_len for the buffer
\discussion After this function call, InsertData() and AppendData() can be called.

---

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