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# VZNegotiatedVirtioFeatureSet

Values that represent a set of negotiated Virtio feature bits.

```
class VZNegotiatedVirtioFeatureSet
```

## Overview

A [`VZNegotiatedVirtioFeatureSet`](/documentation/Virtualization/VZNegotiatedVirtioFeatureSet) represents the set of Virtio features the device and the driver have negotiated.

[`VZNegotiatedVirtioFeatureSet`](/documentation/Virtualization/VZNegotiatedVirtioFeatureSet) encapsulates the 64-bit Virtio feature set as two 32-bit subsets.
The Virtio specification currently supports up to 64 feature bits, where subset0 represents
bits 0 through 31 and subset1 represents bits 32 through 63.

Don’t instantiate [`VZNegotiatedVirtioFeatureSet`](/documentation/Virtualization/VZNegotiatedVirtioFeatureSet) directly. Instead, first configure the device feature
set through the [`mandatoryFeatures`](/documentation/Virtualization/VZCustomVirtioDeviceConfiguration/mandatoryFeatures) and
[`optionalFeatures`](/documentation/Virtualization/VZCustomVirtioDeviceConfiguration/optionalFeatures) properties. Virtio negotiation then
takes place when the guest boots and, after Virtio negotiation completes, the set of negotiated features is
available in the [`negotiatedFeatures`](/documentation/Virtualization/VZCustomVirtioDevice/negotiatedFeatures) property.

## Topics

### Instance Properties

[`var subset0: UInt32`](/documentation/Virtualization/VZNegotiatedVirtioFeatureSet/subset0)

The values that represent feature bits 0 through 31.

[`var subset1: UInt32`](/documentation/Virtualization/VZNegotiatedVirtioFeatureSet/subset1)

The value that represent feature bits 32 through 63.

## Relationships

### Conforms To

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

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

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

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

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

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

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

---

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