Can I bind to a specific host? How is the host option passed through?

Question

RepoPilot · Accepted Answer

Yes, you can bind to a specific host using the `host` option. Here's how it works:

## Host Option Usage

The `host` option is passed directly in the options object:

```js
import getPort from 'get-port';

console.log(await getPort({host: '127.0.0.1'}));
```

According to the documentation, the `host` option can be either an IPv4 or IPv6 address. When set, the library will only check availability on that specific host rather than checking all local addresses [index.d.ts:L29-L36].

## How It's Passed Through

The host option is passed through to the underlying Node.js server listening mechanism. In the main function [index.js:L89-L168], the options are destructured to extract `reserve`, and the remaining options (including `host`) are spread into `netOptions`:

```js
const {reserve, ...netOptions} = options ?? {};
```

These `netOptions` are then passed to `getAvailablePort()` [index.js:L145], which in turn passes them to `checkAvailablePort()` [index.js:L47-L60]. The `checkAvailablePort` function uses these options directly when calling `server.listen(options, ...)` [index.js:L54].

This means the host option flows directly into Node.js's native `net.Server.listen()` method, which handles the actual binding.

FOLLOW_UPS:
- What happens if host is omitted?
- Can you use both host and port together?
- Does host affect the reserve option behavior?