---
title: kIOHIDGCSyntheticDeviceKey
framework: Game Controller
role: symbol
role_heading: Global Variable
path: gamecontroller/kiohidgcsyntheticdevicekey
---

# kIOHIDGCSyntheticDeviceKey

A key that specifies whether the device is a game controller synthetic HID device.

## Declaration

```swift
var kIOHIDGCSyntheticDeviceKey: String { get }
```

## Mentioned in

Understanding game controller backward compatibility

## Discussion

Discussion This key is present with a Boolean value of true on all game controller synthetic HID devices that the Game Controller framework creates. If your app needs to exclude these synthetic HID devices from discovery by IOHIDManagerRef, IOServiceGetMatchingServices(_:_:_:), or IOServiceAddMatchingNotification(_:_:_:_:_:_:), include the kIOHIDGCSyntheticDeviceKey with a value of false in the matching criteria. IOHIDManagerRef manager = IOHIDManagerCreate(kCFAllocatorDefault, kIOHIDManagerOptionNone); IOHIDManagerSetDeviceMatching(manager, (__bridge CFDictionaryRef)@{     @kIOProviderClassKey: @kIOHIDDeviceKey,     @kIOHIDGCSyntheticDeviceKey: @(NO) }); Your code can check whether an io_service_t or an IOHIDDeviceRef refers to a game controller synthetic HID device by querying the value of the kIOHIDGCSyntheticDeviceKey property. if ( IOHIDDeviceGetProperty(device, CFSTR(kIOHIDGCSyntheticDeviceKey)) == kCFBooleanTrue ) {     // This is a synthetic HID device. }

## See Also

### Game Controller framework migration from IOKit

- [Understanding game controller backward compatibility](gamecontroller/understanding-game-controller-backward-compatibility.md)