---
title: IOPacketBufferConstraints
framework: kernel
role: symbol
role_heading: Structure
path: kernel/iopacketbufferconstraints
---

# IOPacketBufferConstraints

## Declaration

```occ
typedef struct IOPacketBufferConstraints {
    ...
} IOPacketBufferConstraints;
```

## Overview

Overview Constraint parameters, specified by a driver, for the data buffer in a packet mbuf. This is observed by allocatePacket() to satisfy the stated requirements.

## Topics

### Instance Properties

- [alignLength](kernel/iopacketbufferconstraints/1393417-alignlength.md)
- [alignStart](kernel/iopacketbufferconstraints/1393367-alignstart.md)
- [reserved](kernel/iopacketbufferconstraints/1393469-reserved.md)

## See Also

### Network Data

- [IONetworkData](kernel/ionetworkdata.md)
- [IONetworkMedium](kernel/ionetworkmedium.md)
- [IOPacketQueue](kernel/iopacketqueue.md)