### Combine Multiple File Systems with unionfs

Source: https://github.com/streamich/unionfs/blob/master/README.md

Shows how to use unionfs to combine multiple file system instances, including Node.js 'fs', 'memfs' Volumes, and a custom 'memory-fs' implementation. This example illustrates reading from different virtual and in-memory file systems.

```javascript
import * as fs from 'fs';
import { Volume } from 'memfs';
import * as MemoryFileSystem from 'memory-fs';
import { ufs } from 'unionfs';

const vol1 = Volume.fromJSON({ '/memfs-1': '1' });
const vol2 = Volume.fromJSON({ '/memfs-2': '2' });

const memoryFs = new MemoryFileSystem();
memoryFs.writeFileSync('/memory-fs', '3');

ufs.use(fs).use(vol1).use(vol2).use(memoryFs);

console.log(ufs.readFileSync('/memfs-1', 'utf8')); // 1
console.log(ufs.readFileSync('/memfs-2', 'utf8')); // 2
console.log(ufs.readFileSync('/memory-fs', 'utf8')); // 3
```

--------------------------------

### Manually Create Union Instance

Source: https://github.com/streamich/unionfs/blob/master/README.md

Illustrates the manual creation of a `Union` instance from the unionfs library. This allows for more granular control over which file systems are included in the union.

```javascript
import { Union } from 'unionfs';

var ufs1 = new Union();
ufs1.use(fs).use(vol);

var ufs2 = new Union();
ufs2.use(fs).use(/*...*/);
```

--------------------------------

### Initialize UnionFS with memfs and Node.js fs

Source: https://github.com/streamich/unionfs/blob/master/README.md

Demonstrates how to initialize unionfs by combining the 'memfs' file system with the standard Node.js 'fs' module. This allows operations to be performed across both virtual and real file systems.

```javascript
import { ufs } from 'unionfs';
import { fs as fs1 } from 'memfs';
import * as fs2 from 'fs';

ufs.use(fs1).use(fs2);

ufs.readFileSync(/* ... */);
```

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