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# searchForRegistrationDomains()

Initiates a search for domains in which the host may register services.

```
func searchForRegistrationDomains()
```

## Discussion

This method returns immediately, sending a [`netServiceBrowserWillSearch(_:)`](/documentation/Foundation/NetServiceBrowserDelegate/netServiceBrowserWillSearch(_:)) message to the delegate if the network was ready to initiate the search. The delegate receives a subsequent [`netServiceBrowser(_:didFindDomain:moreComing:)`](/documentation/Foundation/NetServiceBrowserDelegate/netServiceBrowser(_:didFindDomain:moreComing:)) message for each domain discovered.

Most network service browser clients do not have to use this method—it is sufficient to publish a service with the empty string, which registers it in any available registration domains automatically.

## See Also

[`func netServiceBrowserWillSearch(NetServiceBrowser)`](/documentation/Foundation/NetServiceBrowserDelegate/netServiceBrowserWillSearch(_:))

Tells the delegate that a search is commencing.

[`func netServiceBrowser(NetServiceBrowser, didFindDomain: String, moreComing: Bool)`](/documentation/Foundation/NetServiceBrowserDelegate/netServiceBrowser(_:didFindDomain:moreComing:))

Tells the delegate the sender found a domain.


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