# CMIOExtensionProvider An object that manages device connections for a provider. ``` class CMIOExtensionProvider ``` ## Overview An extension provider manages device connections and provides the [`startService(provider:)`](/documentation/CoreMediaIO/CMIOExtensionProvider/startService(provider:)) class method that you call to bootstrap the service. ## Topics ### Creating a Provider [`+ (instancetype) providerWithSource:(id) source clientQueue:(dispatch_queue_t) clientQueue;`](/documentation/CoreMediaIO/CMIOExtensionProvider/providerWithSource:clientQueue:) Returns a new extension provider with the specified source and dispatch queue. [`init(source: any CMIOExtensionProviderSource, clientQueue: dispatch_queue_t?)`](/documentation/CoreMediaIO/CMIOExtensionProvider/init(source:clientQueue:)) Creates an extension provider with the specified source and dispatch queue. ### Inspecting a Provider [`var clientQueue: dispatch_queue_t`](/documentation/CoreMediaIO/CMIOExtensionProvider/clientQueue) The dispatch queue on which the system performs client operations. [`var source: (any CMIOExtensionProviderSource)?`](/documentation/CoreMediaIO/CMIOExtensionProvider/source) The source for the provider. ### Starting a Provider [`class func startService(provider: CMIOExtensionProvider)`](/documentation/CoreMediaIO/CMIOExtensionProvider/startService(provider:)) Starts the system extension. ### Managing Devices [`var devices: [CMIOExtensionDevice]`](/documentation/CoreMediaIO/CMIOExtensionProvider/devices) An array of connected devices. [`func addDevice(CMIOExtensionDevice) throws`](/documentation/CoreMediaIO/CMIOExtensionProvider/addDevice(_:)) Adds a device to a provider. [`func removeDevice(CMIOExtensionDevice) throws`](/documentation/CoreMediaIO/CMIOExtensionProvider/removeDevice(_:)) Removes a device from a provider. ### Managing Clients [`var connectedClients: [CMIOExtensionClient]`](/documentation/CoreMediaIO/CMIOExtensionProvider/connectedClients) An array of connected clients. [`func notifyPropertiesChanged([CMIOExtensionProperty : CMIOExtensionPropertyState])`](/documentation/CoreMediaIO/CMIOExtensionProvider/notifyPropertiesChanged(_:)) Notifies connected clients of device property changes. ### Type Methods [`class func ignoreSIGTERM()`](/documentation/CoreMediaIO/CMIOExtensionProvider/ignoreSIGTERM()) [`class func stopService(provider: CMIOExtensionProvider)`](/documentation/CoreMediaIO/CMIOExtensionProvider/stopService(provider:)) ## Relationships ### Conforms To [`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible) [`Hashable`](/documentation/Swift/Hashable) [`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol) [`Equatable`](/documentation/Swift/Equatable) [`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible) [`CVarArg`](/documentation/Swift/CVarArg) ### Inherits From [`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class) --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)