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# CFNetwork Data Types

Callback types for various network services.

## Topics

### Data Types

[`typealias CFHostClientCallBack`](/documentation/CFNetwork/CFHostClientCallBack)

Defines a pointer to the callback function that is called when an asynchronous resolution of a CFHost completes or an error occurs for an asynchronous CFHost resolution.

[`typealias CFNetServiceBrowserClientCallBack`](/documentation/CFNetwork/CFNetServiceBrowserClientCallBack)

Defines a pointer to the callback function for a CFNetServiceBrowser.

[`typealias CFNetServiceClientCallBack`](/documentation/CFNetwork/CFNetServiceClientCallBack)

Defines a pointer to the callback function for a CFNetService.

[`typealias CFNetServiceMonitorClientCallBack`](/documentation/CFNetwork/CFNetServiceMonitorClientCallBack)

Defines a pointer to the callback function that is to be called when a monitored record type changes.

[`typealias CFNetDiagnosticStatus`](/documentation/CFNetwork/CFNetDiagnosticStatus)

A CFIndex type that is used to return status values from `CFNetDiagnostic` status and diagnostic functions. For a list of possible values, see [`CFNetDiagnosticStatusValues`](/documentation/CFNetwork/CFNetDiagnosticStatusValues).


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