Makes a CFNetService available on the network.


func CFNetServiceRegisterWithOptions(_ theService: CFNetService, _ options: CFOptionFlags, _ error: UnsafeMutablePointer<CFStreamError>?) -> Bool



Network service to register; cannot be NULL. The registration will fail if the service doesn’t have a domain, a type, a name, and an IP address.


Bit flags for specifying registration options. Currently, the only registration option is kCFNetServiceFlagNoAutoRename. For details, see CFNetService Registration Options.


Pointer to a CFStreamError structure that will be set to an error code and the error code’s domain if an error occurs; or NULL if you don’t want to receive the error code and its domain.

Return Value

TRUE if an asynchronous service registration was started; FALSE if an asynchronous or synchronous registration failed or if a synchronous registration was canceled.


If the service is to run in asynchronous mode, you must call CFNetServiceSetClient(_:_:_:) to associate a callback function with this CFNetService before calling this function.

When registering a service that runs in asynchronous mode, this function returns TRUE if the service contains all of the required attributes and the registration process can start. If the registration process completes successfully, the service is available on the network until you shut down the service by calling CFNetServiceUnscheduleFromRunLoop(_:_:_:), CFNetServiceSetClient(_:_:_:), and CFNetServiceCancel(_:). If the service does not contain all of the required attributes or if the registration process does not complete successfully, this function returns FALSE.

When registering a service that runs in synchronous mode, this function blocks until an error occurs, in which case this function returns FALSE. Until this function returns FALSE, the service is available on the network. To force this function to return FALSE, thereby shutting down the service, call CFNetServiceCancel(_:) from another thread.

The options parameter is a bit flag for specifying service registration options. Currently, kCFNetServiceFlagNoAutoRename is the only supported registration option. If this bit is set and a service of the same name is running, the registration will fail. If this bit is not set and a service of the same name is running, the service that is being registered will be renamed automatically by appending (n) to the service name, where n is a number that is incremented until the service can be registered with a unique name.

Special Considerations

This function is thread safe.

See Also

Network Services

class CFNetService

An opaque reference representing a CFNetService.

class CFNetServiceBrowser

An opaque reference representing a CFNetServiceBrowser.

class CFNetServiceMonitor

An opaque reference for a service monitor.

enum CFNetServiceMonitorType

Record type specifier used to tell a service monitor the type of record changes to watch for.

struct CFNetServiceClientContext

A structure provided when a CFNetService is associated with a callback function or when a CFNetServiceBrowser is created.

enum CFNetServicesError

Error codes that may be returned by CFNetServices functions or passed to CFNetServices callback functions.

func CFNetServiceBrowserInvalidate(CFNetServiceBrowser)

Invalidates an instance of a Network Service browser object.

func CFNetServiceBrowserGetTypeID() -> CFTypeID

Gets the Core Foundation type identifier for the Network Service browser object.

func CFNetServiceBrowserUnscheduleFromRunLoop(CFNetServiceBrowser, CFRunLoop, CFString)

Unschedules a CFNetServiceBrowser from a run loop and mode.

func CFNetServiceCancel(CFNetService)

Cancels a service registration or a service resolution.

func CFNetServiceGetPortNumber(CFNetService) -> Int32

This function gets the port number from a CFNetService.

func CFNetServiceGetTXTData(CFNetService) -> Unmanaged<CFData>?

Queries a network service for the contents of its TXT records.

func CFNetServiceGetTypeID() -> CFTypeID

Gets the Core Foundation type identifier for the Network Service object.

func CFNetServiceMonitorGetTypeID() -> CFTypeID

Gets the Core Foundation type identifier for all CFNetServiceMonitor instances.

func CFNetServiceMonitorInvalidate(CFNetServiceMonitor)

Invalidates an instance of a Network Service monitor object.

func CFNetServiceSetClient(CFNetService, CFNetServiceClientCallBack?, UnsafeMutablePointer<CFNetServiceClientContext>?) -> Bool

Associates a callback function with a CFNetService or disassociates a callback function from a CFNetService.

func CFNetServiceSetTXTData(CFNetService, CFData) -> Bool

Sets the TXT record for a CFNetService.