What is the type signature of the main exported function?

The main exported function getPort has the following type signature [index.d.ts:L66]:

export default function getPort(options?: Options): Promise<number>;

This function takes an optional Options object and returns a Promise that resolves to a port number.

The Options type is defined as [index.d.ts:L3-L65], which includes:

• port?: number | Iterable<number> — A preferred port or iterable of preferred ports
• exclude?: Iterable<number> — Ports to exclude from consideration
• reserve?: boolean — Whether to reserve the port for the lifetime of the process (default: false)
• host?: string — The host on which to check port availability
• Plus additional properties from Node's ListenOptions (minus the port field)

FOLLOW_UPS:

• How does the function handle preferred ports?
• What happens when no ports are available?
• How does the reserve option work internally?