# init(service:targetQueue:options:incomingSessionHandler:) Creates the server side of an XPC service using the specified service name. ``` @preconcurrency init(service: String, targetQueue: DispatchQueue? = nil, options: XPCListener.InitializationOptions = .none, incomingSessionHandler: @escaping @Sendable (XPCListener.IncomingSessionRequest) -> XPCListener.IncomingSessionRequest.Decision) throws ``` ## Parameters `service` The Mach service or XPC service name that clients use to connect to the service. `targetQueue` The dispatch queue that events arrive on. This may be a concurrent queue. If , the listeners uses `DISPATCH_TARGET_QUEUE_DEFAULT`. `options` Configuration options for the listener, such as creating it in an inactive state. `incomingSessionHandler` A handler that the system calls when a client connects to the XPC service. ## Discussion Listener creation fails if the XPC service isn’t found or is unavailable. When a client connects to your service, the system invokes the `incomingSessionHandler` with a request that you must either accept or reject. To accept the incoming request, choose one of the following two approaches: - For simple protocols, use [`accept(incomingMessageHandler:cancellationHandler:)`](/documentation/XPC/XPCListener/IncomingSessionRequest/accept(incomingMessageHandler:cancellationHandler:)-8rodk) or [`accept(incomingMessageHandler:cancellationHandler:)`](/documentation/XPC/XPCListener/IncomingSessionRequest/accept(incomingMessageHandler:cancellationHandler:)-48c3k) to provide a closure that receives the incoming message directly. - For more complex protocols that delegate message handling to a different object, use `accept(_:)` to provide a closure that returns a [`XPCPeerHandler`](/documentation/XPC/XPCPeerHandler). The peer handler object receives incoming messages from the client directly. When the `incomingSessionHandler` returns, the system automatically activates the peer session unless you explicitly reject it or pass the [`inactive`](/documentation/XPC/XPCListener/InitializationOptions/inactive) initialzation option. --- 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)