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# SetTxPacketHeadroom

Reserves the specified number of bytes at the front of each packet.

```
kern_return_t SetTxPacketHeadroom(uint16_t numBytes);
```

## Parameters

`numBytes`

The number of bytes to reserve at the front of the packet buffer.

## Return Value

`kIOReturnSuccess` on success, or another value if an error occurred.

---

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