---
title: negotiatedFeatures
framework: virtualization
role: symbol
role_heading: Instance Property
path: virtualization/vzcustomvirtiodevice/negotiatedfeatures
---

# negotiatedFeatures

The set of features that the driver and the device have successfully negotiated, or nil if no feature negotiation has taken place.

## Declaration

```swift
var negotiatedFeatures: VZNegotiatedVirtioFeatureSet? { get }
```

## Discussion

Discussion The value is only valid after the framework calls customVirtioDeviceDidAcceptDriverOk(_:). The framework calls this method when the guest driver sets DRIVER_OK.