# DNSServiceRegisterReply Handler for the results from a previous call to [`DNSServiceRegister(_:_:_:_:_:_:_:_:_:_:_:_:)`](/documentation/dnssd/DNSServiceRegister(_:_:_:_:_:_:_:_:_:_:_:_:)). ``` typealias DNSServiceRegisterReply = (DNSServiceRef?, DNSServiceFlags, DNSServiceErrorType, UnsafePointer?, UnsafePointer?, UnsafePointer?, UnsafeMutableRawPointer?) -> Void ``` ## Parameters `sdRef` The DNSServiceRef initialized by [`DNSServiceRegister(_:_:_:_:_:_:_:_:_:_:_:_:)`](/documentation/dnssd/DNSServiceRegister(_:_:_:_:_:_:_:_:_:_:_:_:)). `flags` When a name is successfully registered, the callback will be invoked with the kDNSServiceFlagsAdd flag set. When Wide-Area DNS-SD is in use, it is possible for a single service to get more than one success callback (e.g. one in the “local” multicast DNS domain, and another in a wide-area unicast DNS domain). If a successfully-registered name later suffers a name conflict or similar problem and has to be deregistered, the callback will be invoked with the kDNSServiceFlagsAdd flag not set. The callback is *not* invoked in the case where the caller explicitly terminates the service registration by calling DNSServiceRefDeallocate(ref); `errorCode` Will be [`kDNSServiceErr_NoError`](/documentation/dnssd/kDNSServiceErr_NoError) on success, otherwise will indicate the failure that occurred (including name conflicts, if the kDNSServiceFlagsNoAutoRename flag was used when registering.) Other parameters are undefined if errorCode is nonzero. `name` The service name registered (if the application did not specify a name in [`DNSServiceRegister(_:_:_:_:_:_:_:_:_:_:_:_:)`](/documentation/dnssd/DNSServiceRegister(_:_:_:_:_:_:_:_:_:_:_:_:)), this indicates what name was automatically chosen). `regtype` The type of service registered, as it was passed to the callout. `domain` The domain on which the service was registered (if the application did not specify a domain in [`DNSServiceRegister(_:_:_:_:_:_:_:_:_:_:_:_:)`](/documentation/dnssd/DNSServiceRegister(_:_:_:_:_:_:_:_:_:_:_:_:)), this indicates the default domain on which the service was registered). `context` The context pointer that was passed to the callout. --- 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)