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# NWProtocolTCP.Metadata

A handle you can use to inspect a connection’s TCP state.

```
class Metadata
```

## Topics

### Inspecting TCP State

[`var availableSendBuffer: UInt32`](/documentation/Network/NWProtocolTCP/Metadata/availableSendBuffer)

The number of available bytes in the TCP send buffer.

[`var availableReceiveBuffer: UInt32`](/documentation/Network/NWProtocolTCP/Metadata/availableReceiveBuffer)

The number of available bytes in the TCP receive buffer.

### Instance Methods

[`func setMaximumPacingRateBytesPerSecond(UInt64?)`](/documentation/Network/NWProtocolTCP/Metadata/setMaximumPacingRateBytesPerSecond(_:))

Set the maximum pacing rate for this TCP connection, in bytes per second.

## Relationships

### Conforms To

[`Sendable`](/documentation/Swift/Sendable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

### Inherits From

[`NWProtocolMetadata`](/documentation/Network/NWProtocolMetadata)

---

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