# Technical Documentation: jprichardson/node-fs-extra

> ℹ️ **Provenance:** Multi-Tier Ingestion · [CodeWiki Reference](https://codewiki.google/github.com/jprichardson/node-fs-extra)

### Overview (`README.md`)

Node.js: fs-extra
=================

`fs-extra` adds file system methods that aren't included in the native `fs` module and adds promise support to the `fs` methods. It also uses [`graceful-fs`](https://github.com/isaacs/node-graceful-fs) to prevent `EMFILE` errors. It should be a drop in replacement for `fs`.

[](https://www.npmjs.org/package/fs-extra)
[](https://github.com/jprichardson/node-fs-extra/blob/master/LICENSE)
[](https://github.com/jprichardson/node-fs-extra/actions/workflows/ci.yml?query=branch%3Amaster)
[](https://www.npmjs.org/package/fs-extra)
[](https://standardjs.com)

Why?
----

I got tired of including `mkdirp`, `rimraf`, and `ncp` in most of my projects.




Installation
------------

    npm install fs-extra



Usage
-----

### CommonJS

`fs-extra` is a drop in replacement for native `fs`. All methods in `fs` are attached to `fs-extra`. All `fs` methods return promises if the callback isn't passed.

You don't ever need to include the original `fs` module again:

```js
const fs = require('fs') // this is no longer necessary
```

you can now do this:

```js
const fs = require('fs-extra')
```

or if you prefer to make it clear that you're using `fs-extra` and not `fs`, you may want
to name your `fs` variable `fse` like so:

```js
const fse = require('fs-extra')
```

you can also keep both, but it's redundant:

```js
const fs = require('fs')
const fse = require('fs-extra')
```

**NOTE:** The deprecated constants `fs.F_OK`, `fs.R_OK`, `fs.W_OK`, & `fs.X_OK` are not exported on Node.js v24.0.0+; please use their `fs.constants` equivalents. 

### ESM

There is also an `fs-extra/esm` import, that supports both default and named exports. However, note that `fs` methods are not included in `fs-extra/esm`; you still need to import `fs` and/or `fs/promises` separately:

```js
import { readFileSync } from 'fs'
import { readFile } from 'fs/promises'
import { outputFile, outputFileSync } from 'fs-extra/esm'
```

Default exports are supported:

```js
import fs from 'fs'
import fse from 'fs-extra/esm'
// fse.readFileSync is not a function; must use fs.readFileSync
```

but you probably want to just use regular `fs-extra` instead of `fs-extra/esm` for default exports:

```js
import fs from 'fs-extra'
// both fs and fs-extra methods are defined
```

Sync vs Async vs Async/Await
-------------
Most methods are async by default. All async methods will return a promise if the callback isn't passed.

Sync methods on the other hand will throw if an error occurs.

Also Async/Await will throw an error if one occurs.

Example:

```js
const fs = require('fs-extra')

// Async with promises:
fs.copy('/tmp/myfile', '/tmp/mynewfile')
  .then(() => console.log('success!'))
  .catch(err => console.error(err))

// Async with callbacks:
fs.copy('/tmp/myfile', '/tmp/mynewfile', err => {
  if (err) return console.error(err)
  console.log('success!')
})

// Sync:
try {
  fs.copySync('/tmp/myfile', '/tmp/mynewfile')
  console.log('success!')
} catch (err) {
  console.error(err)
}

// Async/Await:
async function copyFiles () {
  try {
    await fs.copy('/tmp/myfile', '/tmp/mynewfile')
    console.log('success!')
  } catch (err) {
    console.error(err)
  }
}

copyFiles()
```


Methods
-------

### Async

- [copy](docs/copy.md)
- [emptyDir](docs/emptyDir.md)
- [ensureFile](docs/ensureFile.md)
- [ensureDir](docs/ensureDir.md)
- [ensureLink](docs/ensureLink.md)
- [ensureSymlink](docs/ensureSymlink.md)
- [mkdirp](docs/ensureDir.md)
- [mkdirs](docs/ensureDir.md)
- [move](docs/move.md)
- [outputFile](docs/outputFile.md)
- [outputJson](docs/outputJson.md)
- [pathExists](docs/pathExists.md)
- [readJson](docs/readJson.md)
- [remove](docs/remove.md)
- [writeJson](docs/writeJson.md)

### Sync

- [copySync](docs/copy-sync.md)
- [emptyDirSync](docs/emptyDir-sync.md)
- [ensureFileSync](docs/ensureFile-sync.md)
- [ensureDirSync](docs/ensureDir-sync.md)
- [ensureLinkSync](docs/ensureLink-sync.md)
- [ensureSymlinkSync](docs/ensureSymlink-sync.md)
- [mkdirpSync](docs/ensureDir-sync.md)
- [mkdirsSync](docs/ensureDir-sync.md)
- [moveSync](docs/move-sync.md)
- [outputFileSync](docs/outputFile-sync.md)
- [outputJsonSync](docs/outputJson-sync.md)
- [pathExistsSync](docs/pathExists-sync.md)
- [readJsonSync](docs/readJson-sync.md)
- [removeSync](docs/remove-sync.md)
- [writeJsonSync](docs/writeJson-sync.md)


**NOTE:** You can still use the native Node.js methods. They are promisified and copied over to `fs-extra`. See [notes on `fs.read()`, `fs.write()`, & `fs.writev()`](docs/fs-read-write-writev.md)

### What happened to `walk()` and `walkSync()`?

They were removed from `fs-extra` in v2.0.0. If you need the functionality, `walk` and `walkSync` are available as separate packages, [`klaw`](https://github.com/jprichardson/node-klaw) and [`klaw-sync`](https://github.com/manidlou/node-klaw-sync).


Third Party
-----------

### CLI

[fse-cli](https://www.npmjs.com/package/@atao60/fse-cli) allows you to run `fs-extra` from a console or from [npm](https://www.npmjs.com) scripts.

### TypeScript

If you like TypeScript, you can use `fs-extra` with it: https://github.com/DefinitelyTyped/DefinitelyTyped/tree/master/types/fs-extra


### File / Directory Watching

If you want to watch for changes to files or directories, then you should use [chokidar](https://github.com/paulmillr/chokidar).

### Obtain Filesystem (Devices, Partitions) Information

[fs-filesystem](https://github.com/arthurintelligence/node-fs-filesystem) allows you to read the state of the filesystem of the host on which it is run. It returns information about both the devices and the partitions (volumes) of the system.

### Misc.

- [fs-extra-debug](https://github.com/jdxcode/fs-extra-debug) - Send your fs-extra calls to [debug](https://npmjs.org/package/debug).
- [mfs](https://github.com/cadorn/mfs) - Monitor your fs-extra calls.



Hacking on fs-extra
-------------------

Wanna hack on `fs-extra`? Great! Your help is needed! [fs-extra is one of the most depended upon Node.js packages](http://nodei.co/npm/fs-extra.png?downloads=true&downloadRank=true&stars=true). This project
uses [JavaScript Standard Style](https://github.com/feross/standard) - if the name or style choices bother you,
you're gonna have to get over it :) If `standard` is good enough for `npm`, it's good enough for `fs-extra`.

[](https://github.com/feross/standard)

What's needed?
- First, take a look at existing issues. Those are probably going to be where the priority lies.
- More tests for edge cases. Specifically on different platforms. There can never be enough tests.
- Improve test coverage.

Note: If you make any big changes, **you should definitely file an issue for discussion first.**

### Running the Test Suite

fs-extra contains hundreds of tests.

- `npm run lint`: runs the linter ([standard](http://standardjs.com/))
- `npm run unit`: runs the unit tests
- `npm run unit-esm`: runs tests for `fs-extra/esm` exports
- `npm test`: runs the linter and all tests

When running unit tests, set the environment variable `CROSS_DEVICE_PATH` to the absolute path of an empty directory on another device (like a thumb drive) to enable cross-device move tests.


### Windows

If you run the tests on the Windows and receive a lot of symbolic link `EPERM` permission errors, it's
because on Windows you need elevated privilege to create symbolic links. You can add this to your Windows's
account by following the instructions here: http://superuser.com/questions/104845/permission-to-make-symbolic-links-in-windows-7
However, I didn't have much luck doing this.

Since I develop on Mac OS X, I use VMWare Fusion for Windows testing. I create a shared folder that I map to a drive on Windows.
I open the `Node.js command prompt` and run as `Administrator`. I then map the network drive running the following command:

    net use z: "\\vmware-host\Shared Folders"

I can then navigate to my `fs-extra` directory and run the tests.


Naming
------

I put a lot of thought into the naming of these functions. Inspired by @coolaj86's request. So he deserves much of the credit for raising the issue. See discussion(s) here:

* https://github.com/jprichardson/node-fs-extra/issues/2
* https://github.com/flatiron/utile/issues/11
* https://github.com/ryanmcgrath/wrench-js/issues/29
* https://github.com/substack/node-mkdirp/issues/17

First, I believe that in as many cases as possible, the [Node.js naming schemes](http://nodejs.org/api/fs.html) should be chosen. However, there are problems with the Node.js own naming schemes.

For example, `fs.readFile()` and `fs.readdir()`: the **F** is capitalized in *File* and the **d** is not capitalized in *dir*. Perhaps a bit pedantic, but they should still be consistent. Also, Node.js has chosen a lot of POSIX naming schemes, which I believe is great. See: `fs.mkdir()`, `fs.rmdir()`, `fs.chown()`, etc.

We have a dilemma though. How do you consistently name methods that perform the following POSIX commands: `cp`, `cp -r`, `mkdir -p`, and `rm -rf`?

My perspective: when in doubt, err on the side of simplicity. A directory is just a hierarchical grouping of directories and files. Consider that for a moment. So when you want to copy it or remove it, in most cases you'll want to copy or remove all of its contents. When you want to create a directory, if the directory that it's suppose to be contained in does not exist, then in most cases you'll want to create that too.

So, if you want to remove a file or a directory regardless of whether it has contents, just call `fs.remove(path)`. If you want to copy a file or a directory whether it has contents, just call `fs.copy(source, destination)`. If you want to create a directory regardless of whether its parent directories exist, just call `fs.mkdirs(path)` or `fs.mkdirp(path)`.


Credit
------

`fs-extra` wouldn't be possible without using the modules from the following authors:

- [Isaac Shlueter](https://github.com/isaacs)
- [Charlie McConnel](https://github.com/avianflu)
- [Andrew Kelley](https://github.com/andrewrk)




License
-------

Licensed under MIT

Copyright (c) 2011-2024 [JP Richardson](https://github.com/jprichardson)

[1]: http://nodejs.org/docs/latest/api/fs.html


[jsonfile]: https://github.com/jprichardson/node-jsonfile

---

### Overview (`test/readme.md`)

Looking for the test files? You can find all of the test files in `lib/**/__tests__`.

---

### Overview (`lib/copy/__tests__/ncp/README.md`)

These tests came from: https://github.com/AvianFlu/ncp/tree/v1.0.1/test

---

### Copy Sync (`docs/copy-sync.md`)

# copySync(src, dest[, options])

Copy a file or directory. The directory can have contents.

- `src` `<String>` Note that if `src` is a directory it will copy everything inside of this directory, not the entire directory itself (see [issue #537](https://github.com/jprichardson/node-fs-extra/issues/537)).
- `dest` `<String>` Note that if `src` is a file, `dest` cannot be a directory (see [issue #323](https://github.com/jprichardson/node-fs-extra/issues/323)).
- `options` `<Object>`
  - `overwrite` `<boolean>`: overwrite existing file or directory, default is `true`. _Note that the copy operation will silently fail if you set this to `false` and the destination exists._ Use the `errorOnExist` option to change this behavior.
  - `errorOnExist` `<boolean>`: when `overwrite` is `false` and the destination exists, throw an error. Default is `false`.
  - `dereference` `<boolean>`: dereference symlinks, default is `false`.
  - `preserveTimestamps` `<boolean>`: When true, will set last modification and access times to the ones of the original source files. When false, timestamp behavior is OS-dependent. Default is `false`.
  - `filter` `<Function>`: Function to filter copied files/directories. Return `true` to copy the item, `false` to ignore it.

## Example:

```js
const fs = require('fs-extra')

// copy file
fs.copySync('/tmp/myfile', '/tmp/mynewfile')

// copy directory, even if it has subdirectories or files
fs.copySync('/tmp/mydir', '/tmp/mynewdir')
```

**Using filter function**

```js
const fs = require('fs-extra')

const filterFunc = (src, dest) => {
  // your logic here
  // it will be copied if return true
}

fs.copySync('/tmp/mydir', '/tmp/mynewdir', { filter: filterFunc })
```

---

### Copy (`docs/copy.md`)

# copy(src, dest[, options][, callback])

Copy a file or directory. The directory can have contents.

- `src` `<String>` Note that if `src` is a directory it will copy everything inside of this directory, not the entire directory itself (see [issue #537](https://github.com/jprichardson/node-fs-extra/issues/537)).
- `dest` `<String>` Note that if `src` is a file, `dest` cannot be a directory (see [issue #323](https://github.com/jprichardson/node-fs-extra/issues/323)).
- `options` `<Object>`
  - `overwrite` `<boolean>`: overwrite existing file or directory, default is `true`. _Note that the copy operation will silently fail if you set this to `false` and the destination exists._ Use the `errorOnExist` option to change this behavior.
  - `errorOnExist` `<boolean>`: when `overwrite` is `false` and the destination exists, throw an error. Default is `false`.
  - `dereference` `<boolean>`: dereference symlinks, default is `false`.
  - `preserveTimestamps` `<boolean>`: When true, will set last modification and access times to the ones of the original source files. When false, timestamp behavior is OS-dependent. Default is `false`.
  - `filter` `<Function>`: Function to filter copied files/directories. Return `true` to copy the item, `false` to ignore it. Can also return a `Promise` that resolves to `true` or `false` (or pass in an `async` function).
- `callback` `<Function>`
  - `err` `<Error>`

## Example:

```js
const fs = require('fs-extra')

// With a callback:
fs.copy('/tmp/myfile', '/tmp/mynewfile', err => {
  if (err) return console.error(err)
  console.log('success!')
}) // copies file

fs.copy('/tmp/mydir', '/tmp/mynewdir', err => {
  if (err) return console.error(err)
  console.log('success!')
}) // copies directory, even if it has subdirectories or files

// With Promises:
fs.copy('/tmp/myfile', '/tmp/mynewfile')
.then(() => {
  console.log('success!')
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example () {
  try {
    await fs.copy('/tmp/myfile', '/tmp/mynewfile')
    console.log('success!')
  } catch (err) {
    console.error(err)
  }
}

example()
```

**Using filter function**

```js
const fs = require('fs-extra')

const filterFunc = (src, dest) => {
  // your logic here
  // it will be copied if return true
}

fs.copy('/tmp/mydir', '/tmp/mynewdir', { filter: filterFunc }, err => {
  if (err) return console.error(err)
  console.log('success!')
})
```

---

### EmptyDir Sync (`docs/emptyDir-sync.md`)

# emptyDirSync(dir)

Ensures that a directory is empty. Deletes directory contents if the directory is not empty. If the directory does not exist, it is created. The directory itself is not deleted.

**Alias:** `emptydirSync()`

- `dir` `<String>`

## Example:

```js
const fs = require('fs-extra')

// assume this directory has a lot of files and folders
fs.emptyDirSync('/tmp/some/dir')
```

---

### EmptyDir (`docs/emptyDir.md`)

# emptyDir(dir[, callback])

Ensures that a directory is empty. Deletes directory contents if the directory is not empty. If the directory does not exist, it is created. The directory itself is not deleted.

**Alias:** `emptydir()`

- `dir` `<String>`
- `callback` `<Function>`
  - `err` `<Error>`

## Example:

```js
const fs = require('fs-extra')

// assume this directory has a lot of files and folders
// With a callback:
fs.emptyDir('/tmp/some/dir', err => {
  if (err) return console.error(err)
  console.log('success!')
})

// With Promises:
fs.emptyDir('/tmp/some/dir')
.then(() => {
  console.log('success!')
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example () {
  try {
    await fs.emptyDir('/tmp/some/dir')
    console.log('success!')
  } catch (err) {
    console.error(err)
  }
}

example()
```

---

### EnsureDir Sync (`docs/ensureDir-sync.md`)

# ensureDirSync(dir[,options])

Ensures that the directory exists. If the directory structure does not exist, it is created. If provided, options may specify the desired mode for the directory. 

**Aliases:** `mkdirsSync()`, `mkdirpSync()`

- `dir` `<String>`
- `options` `<Integer> | <Object>`
  - If it is `Integer`, it will be `mode`.
  - If it is `Object`, it will be `{ mode: <Integer> }`.

## Example:

```js
const fs = require('fs-extra')

const dir = '/tmp/this/path/does/not/exist'

const desiredMode = 0o2775
const options = {
  mode: 0o2775
}

fs.ensureDirSync(dir)
// dir has now been created, including the directory it is to be placed in

fs.ensureDirSync(dir, desiredMode)
// dir has now been created, including the directory it is to be placed in with permission 0o2775

fs.ensureDirSync(dir, options)
// dir has now been created, including the directory it is to be placed in with permission 0o2775
```

---

### EnsureDir (`docs/ensureDir.md`)

# ensureDir(dir[,options][,callback])

Ensures that the directory exists. If the directory structure does not exist, it is created.

**Aliases:** `mkdirs()`, `mkdirp()`

- `dir` `<String>`
- `options` `<Integer> | <Object>`
  - If it is `Integer`, it will be `mode`.
  - If it is `Object`, it will be `{ mode: <Integer> }`.
- `callback` `<Function>`
  - `err` `<Error>`

## Example:

```js
const fs = require('fs-extra')

const dir = '/tmp/this/path/does/not/exist'
const desiredMode = 0o2775
const options = {
  mode: 0o2775
}

// With a callback:
fs.ensureDir(dir, err => {
  console.log(err) // => null
  // dir has now been created, including the directory it is to be placed in
})

// With a callback and a mode integer
fs.ensureDir(dir, desiredMode, err => {
  console.log(err) // => null
  // dir has now been created with mode 0o2775, including the directory it is to be placed in
})

// With Promises:
fs.ensureDir(dir)
.then(() => {
  console.log('success!')
})
.catch(err => {
  console.error(err)
})

// With Promises and a mode integer:
fs.ensureDir(dir, desiredMode)
.then(() => {
  console.log('success!')
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example (directory) {
  try {
    await fs.ensureDir(directory)
    console.log('success!')
  } catch (err) {
    console.error(err)
  }
}
example(dir)

// With async/await and an options object, containing mode:
async function exampleMode (directory) {
  try {
    await fs.ensureDir(directory, options)
    console.log('success!')
  } catch (err) {
    console.error(err)
  }
}
exampleMode(dir)
```

---

### EnsureFile Sync (`docs/ensureFile-sync.md`)

# ensureFileSync(file)

Ensures that the file exists. If the file that is requested to be created is in directories that do not exist, these directories are created. If the file already exists, it is **NOT MODIFIED**.

**Alias:** `createFileSync()`

- `file` `<String>`

## Example:

```js
const fs = require('fs-extra')

const file = '/tmp/this/path/does/not/exist/file.txt'
fs.ensureFileSync(file)
// file has now been created, including the directory it is to be placed in
```

---

### EnsureFile (`docs/ensureFile.md`)

# ensureFile(file[, callback])

Ensures that the file exists. If the file that is requested to be created is in directories that do not exist, these directories are created. If the file already exists, it is **NOT MODIFIED**.

**Alias:** `createFile()`

- `file` `<String>`
- `callback` `<Function>`
  - `err` `<Error>`

## Example:

```js
const fs = require('fs-extra')

const file = '/tmp/this/path/does/not/exist/file.txt'

// With a callback:
fs.ensureFile(file, err => {
  console.log(err) // => null
  // file has now been created, including the directory it is to be placed in
})

// With Promises:
fs.ensureFile(file)
.then(() => {
  console.log('success!')
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example (f) {
  try {
    await fs.ensureFile(f)
    console.log('success!')
  } catch (err) {
    console.error(err)
  }
}

example(file)
```

---

### EnsureLink Sync (`docs/ensureLink-sync.md`)

# ensureLinkSync(srcPath, destPath)

Ensures that the link exists. If the directory structure does not exist, it is created.

**Alias:** `createLinkSync()`

- `srcPath` `<String>`
- `destPath` `<String>`

## Example:

```js
const fs = require('fs-extra')

const srcPath = '/tmp/file.txt'
const destPath = '/tmp/this/path/does/not/exist/file.txt'
fs.ensureLinkSync(srcPath, destPath)
// link has now been created, including the directory it is to be placed in
```

---

### EnsureLink (`docs/ensureLink.md`)

# ensureLink(srcPath, destPath[, callback])

Ensures that the link exists. If the directory structure does not exist, it is created.

**Alias:** `createLink()`

- `srcPath` `<String>`
- `destPath` `<String>`
- `callback` `<Function>`
  - `err` `<Error>`

## Example:

```js
const fs = require('fs-extra')

const srcPath = '/tmp/file.txt'
const destPath = '/tmp/this/path/does/not/exist/file.txt'

// With a callback:
fs.ensureLink(srcPath, destPath, err => {
  console.log(err) // => null
  // link has now been created, including the directory it is to be placed in
})

// With Promises:
fs.ensureLink(srcPath, destPath)
.then(() => {
  console.log('success!')
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example (src, dest) {
  try {
    await fs.ensureLink(src, dest)
    console.log('success!')
  } catch (err) {
    console.error(err)
  }
}

example(srcPath, destPath)
```

---

### EnsureSymlink Sync (`docs/ensureSymlink-sync.md`)

# ensureSymlinkSync(srcPath, destPath[, type])

Ensures that the symlink exists. If the directory structure does not exist, it is created.

**Alias:** `createSymlinkSync()`

- `srcPath` `<String>`
- `destPath` `<String>`
- `type` `<String>` It is only available on Windows and ignored on other platforms. It can be set to `dir`, `file`, or `junction`.

## Example:

```js
const fs = require('fs-extra')

const srcPath = '/tmp/file.txt'
const destPath = '/tmp/this/path/does/not/exist/file.txt'
fs.ensureSymlinkSync(srcPath, destPath)
// symlink has now been created, including the directory it is to be placed in
```

---

### EnsureSymlink (`docs/ensureSymlink.md`)

# ensureSymlink(srcPath, destPath[, type][, callback])

Ensures that the symlink exists. If the directory structure does not exist, it is created.

**Alias:** `createSymlink()`

- `srcPath` `<String>`
- `destPath` `<String>`
- `type` `<String>` It is only available on Windows and ignored on other platforms. It can be set to `dir`, `file`, or `junction`.
- `callback` `<Function>`
  - `err` `<Error>`

## Example:

```js
const fs = require('fs-extra')

const srcPath = '/tmp/file.txt'
const destPath = '/tmp/this/path/does/not/exist/file.txt'

// With a callback:
fs.ensureSymlink(srcPath, destPath, err => {
  console.log(err) // => null
  // symlink has now been created, including the directory it is to be placed in
})

// With Promises:
fs.ensureSymlink(srcPath, destPath)
.then(() => {
  console.log('success!')
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example (src, dest) {
  try {
    await fs.ensureSymlink(src, dest)
    console.log('success!')
  } catch (err) {
    console.error(err)
  }
}

example(srcPath, destPath)
```

---

### Fs Read Write Writev (`docs/fs-read-write-writev.md`)

# About `fs.read()` & `fs.write()`

[`fs.read()`](https://nodejs.org/api/fs.html#fs_fs_read_fd_buffer_offset_length_position_callback), [`fs.write()`](https://nodejs.org/api/fs.html#fs_fs_write_fd_buffer_offset_length_position_callback), & [`fs.writev()`](https://nodejs.org/api/fs.html#fs_fs_writev_fd_buffers_position_callback) are different from other `fs` methods in that their callbacks are called with 3 arguments instead of the usual 2 arguments.

If you're using them with callbacks, they will behave as usual. However, their promise usage is a little different. `fs-extra` promisifies these methods like [`util.promisify()`](https://nodejs.org/api/util.html#util_util_promisify_original) does.

Here's the example promise usage:

## `fs.read()`

```js
// With Promises:
fs.read(fd, buffer, offset, length, position)
  .then(results => {
    console.log(results)
    // { bytesRead: 20, buffer: <Buffer 0f 34 5d ...> }
  })

// With async/await:
async function example () {
  const { bytesRead, buffer } = await fs.read(fd, Buffer.alloc(length), offset, length, position)
}
```

## `fs.write()`

```js
// With Promises:
fs.write(fd, buffer, offset, length, position)
  .then(results => {
    console.log(results)
    // { bytesWritten: 20, buffer: <Buffer 0f 34 5d ...> }
  })

// With async/await:
async function example () {
  const { bytesWritten, buffer } = await fs.write(fd, Buffer.alloc(length), offset, length, position)
}
```

## `fs.writev()`

```js
// With async/await:
async function example () {
  const { bytesWritten, buffers } = await fs.writev(fd, buffers, position)
}
```

---

### Move Sync (`docs/move-sync.md`)

# moveSync(src, dest[, options])

Moves a file or directory, even across devices.

- `src` `<String>`
- `dest` `<String>` Note: When `src` is a file, `dest` must be a file and when `src` is a directory, `dest` must be a directory.
- `options` `<Object>`
  - `overwrite` `<boolean>`: overwrite existing file or directory, default is `false`.

## Example:

```js
const fs = require('fs-extra')

fs.moveSync('/tmp/somefile', '/tmp/does/not/exist/yet/somefile')
```

**Using `overwrite` option**

```js
const fs = require('fs-extra')

fs.moveSync('/tmp/somedir', '/tmp/may/already/exist/somedir', { overwrite: true })
```

---

### Move (`docs/move.md`)

# move(src, dest[, options][, callback])

Moves a file or directory, even across devices.

- `src` `<String>`
- `dest` `<String>` Note: When `src` is a file, `dest` must be a file and when `src` is a directory, `dest` must be a directory.
- `options` `<Object>`
  - `overwrite` `<boolean>`: overwrite existing file or directory, default is `false`.
- `callback` `<Function>`
  - `err` `<Error>`

## Example:

```js
const fs = require('fs-extra')

const src = '/tmp/file.txt'
const dest = '/tmp/this/path/does/not/exist/file.txt'

// With a callback:
fs.move(src, dest, err => {
  if (err) return console.error(err)
  console.log('success!')
})

// With Promises:
fs.move(src, dest)
.then(() => {
  console.log('success!')
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example (src, dest) {
  try {
    await fs.move(src, dest)
    console.log('success!')
  } catch (err) {
    console.error(err)
  }
}

example(src, dest)
```

**Using `overwrite` option**

```js
const fs = require('fs-extra')

fs.move('/tmp/somedir', '/tmp/may/already/exist/somedir', { overwrite: true }, err => {
  if (err) return console.error(err)
  console.log('success!')
})
```

---

### OutputFile Sync (`docs/outputFile-sync.md`)

# outputFileSync(file, data[, options])

Almost the same as `writeFileSync` (i.e. it overwrites), except that if the parent directory does not exist, it's created. `file` must be a file path (a buffer or a file descriptor is not allowed).

- `file` `<String>`
- `data` `<String> | <Buffer> | <Uint8Array>`
- `options` `<Object> | <String>` (the same as [`fs.writeFileSync()` options](https://nodejs.org/api/fs.html#fs_fs_writefilesync_file_data_options))

## Example:

```js
const fs = require('fs-extra')

const file = '/tmp/this/path/does/not/exist/file.txt'
fs.outputFileSync(file, 'hello!')

const data = fs.readFileSync(file, 'utf8')
console.log(data) // => hello!
```

---

### OutputFile (`docs/outputFile.md`)

# outputFile(file, data[, options][, callback])

Almost the same as `writeFile` (i.e. it overwrites), except that if the parent directory does not exist, it's created. `file` must be a file path (a buffer or a file descriptor is not allowed).

- `file` `<String>`
- `data` `<String> | <Buffer> | <Uint8Array>`
- `options` `<Object> | <String>` (the same as [`fs.writeFile()` options](https://nodejs.org/api/fs.html#fs_fs_writefile_file_data_options_callback))
- `callback` `<Function>`
  - `err` `<Error>`

## Example:

```js
const fs = require('fs-extra')

const file = '/tmp/this/path/does/not/exist/file.txt'

// With a callback:
fs.outputFile(file, 'hello!', err => {
  console.log(err) // => null

  fs.readFile(file, 'utf8', (err, data) => {
    if (err) return console.error(err)
    console.log(data) // => hello!
  })
})

// With Promises:
fs.outputFile(file, 'hello!')
.then(() => fs.readFile(file, 'utf8'))
.then(data => {
  console.log(data) // => hello!
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example (f) {
  try {
    await fs.outputFile(f, 'hello!')

    const data = await fs.readFile(f, 'utf8')

    console.log(data) // => hello!
  } catch (err) {
    console.error(err)
  }
}

example(file)
```

---

### OutputJson Sync (`docs/outputJson-sync.md`)

# outputJsonSync(file, object[, options])

Almost the same as [`writeJsonSync`](writeJson-sync.md), except that if the directory does not exist, it's created.

**Alias:** `outputJSONSync()`

- `file` `<String>`
- `object` `<Object>`
- `options` `<Object>`
  - `spaces` `<Number> | <String>` Number of spaces to indent; or a string to use for indentation (i.e. pass `'\t'` for tab indentation). See [the docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#The_space_argument) for more info.
  - `EOL` `<String>` Set EOL character. Default is `\n`.
  - `replacer` [JSON replacer](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#The_replacer_parameter)
  - Also accepts [`fs.writeFileSync()` options](https://nodejs.org/api/fs.html#fs_fs_writefilesync_file_data_options)

## Example:

```js
const fs = require('fs-extra')

const file = '/tmp/this/path/does/not/exist/file.json'
fs.outputJsonSync(file, {name: 'JP'})

const data = fs.readJsonSync(file)
console.log(data.name) // => JP
```

---

### OutputJson (`docs/outputJson.md`)

# outputJson(file, object[, options][, callback])

Almost the same as [`writeJson`](writeJson.md), except that if the directory does not exist, it's created.

**Alias:** `outputJSON()`

- `file` `<String>`
- `object` `<Object>`
- `options` `<Object>`
  - `spaces` `<Number> | <String>` Number of spaces to indent; or a string to use for indentation (i.e. pass `'\t'` for tab indentation). See [the docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#The_space_argument) for more info.
  - `EOL` `<String>` Set EOL character. Default is `\n`.
  - `replacer` [JSON replacer](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#The_replacer_parameter)
  - Also accepts [`fs.writeFile()` options](https://nodejs.org/api/fs.html#fs_fs_writefile_file_data_options_callback)
- `callback` `<Function>`
  - `err` `<Error>`

## Example:

```js
const fs = require('fs-extra')

const file = '/tmp/this/path/does/not/exist/file.json'

// With a callback:
fs.outputJson(file, {name: 'JP'}, err => {
  console.log(err) // => null

  fs.readJson(file, (err, data) => {
    if (err) return console.error(err)
    console.log(data.name) // => JP
  })
})

// With Promises:
fs.outputJson(file, {name: 'JP'})
.then(() => fs.readJson(file))
.then(data => {
  console.log(data.name) // => JP
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example (f) {
  try {
    await fs.outputJson(f, {name: 'JP'})

    const data = await fs.readJson(f)

    console.log(data.name) // => JP
  } catch (err) {
    console.error(err)
  }
}

example(file)
```

---

### PathExists Sync (`docs/pathExists-sync.md`)

# pathExistsSync(file)

An alias for [`fs.existsSync()`](https://nodejs.org/api/fs.html#fs_fs_existssync_path), created for consistency with [`pathExists()`](pathExists.md).

---

### PathExists (`docs/pathExists.md`)

# pathExists(file[, callback])

Test whether or not the given path exists by checking with the file system. Like [`fs.exists`](https://nodejs.org/api/fs.html#fs_fs_exists_path_callback), but with a normal callback signature (err, exists). Uses `fs.access` under the hood.

- `file` `<String>`
- `callback` `<Function>`
  - `err` `<Error>`
  - `exists` `<boolean>`

## Example:

```js
const fs = require('fs-extra')

const file = '/tmp/this/path/does/not/exist/file.txt'

// With a callback:
fs.pathExists(file, (err, exists) => {
  console.log(err) // => null
  console.log(exists) // => false
})

// Promise usage:
fs.pathExists(file)
  .then(exists => console.log(exists)) // => false

// With async/await:
async function example (f) {
  const exists = await fs.pathExists(f)

  console.log(exists) // => false
}

example(file)
```

---

### ReadJson Sync (`docs/readJson-sync.md`)

# readJsonSync(file[, options])

Reads a JSON file and then parses it into an object.

**Alias:** `readJSONSync()`

- `file` `<String>`
- `options` `<Object>` (the same as [`jsonFile.readFileSync()` options](https://github.com/jprichardson/node-jsonfile#readfilesyncfilename-options))

## Example:

```js
const fs = require('fs-extra')

const packageObj = fs.readJsonSync('./package.json')
console.log(packageObj.version) // => 2.0.0
```

---

`readJsonSync()` can take a `throws` option set to `false` and it won't throw if the JSON is invalid. Example:

```js
const fs = require('fs-extra')

const file = '/tmp/some-invalid.json'
const data = '{not valid JSON'
fs.writeFileSync(file, data)

const obj = fs.readJsonSync(file, { throws: false })
console.log(obj) // => null
```

---

### ReadJson (`docs/readJson.md`)

# readJson(file[, options][, callback])

Reads a JSON file and then parses it into an object.

**Alias:** `readJSON()`

- `file` `<String>`
- `options` `<Object>` (the same as [`jsonFile.readFile()` options](https://github.com/jprichardson/node-jsonfile#readfilefilename-options-callback))
- `callback` `<Function>`
  - `err` `<Error>`
  - `obj` `<Object>`

## Example:

```js
const fs = require('fs-extra')

// With a callback:
fs.readJson('./package.json', (err, packageObj) => {
  if (err) console.error(err)
  console.log(packageObj.version) // => 0.1.3
})

// With Promises:
fs.readJson('./package.json')
.then(packageObj => {
  console.log(packageObj.version) // => 0.1.3
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example () {
  try {
    const packageObj = await fs.readJson('./package.json')
    console.log(packageObj.version) // => 0.1.3
  } catch (err) {
    console.error(err)
  }
}

example()
```

---

`readJson()` can take a `throws` option set to `false` and it won't throw if the JSON is invalid. Example:

```js
const fs = require('fs-extra')

const file = '/tmp/some-invalid.json'
const data = '{not valid JSON'
fs.writeFileSync(file, data)

// With a callback:
fs.readJson(file, { throws: false }, (err, obj) => {
  if (err) console.error(err)
  console.log(obj) // => null
})

// With Promises:
fs.readJson(file, { throws: false })
.then(obj => {
  console.log(obj) // => null
})
.catch(err => {
  console.error(err) // Not called
})

// With async/await:
async function example (f) {
  const obj = await fs.readJson(f, { throws: false })
  console.log(obj) // => null
}

example(file)
```

---

### Remove Sync (`docs/remove-sync.md`)

# removeSync(path)

Removes a file or directory. The directory can have contents. If the path does not exist, silently does nothing.

- `path` `<String>`

## Example:

```js
const fs = require('fs-extra')

// remove file
fs.removeSync('/tmp/myfile')

fs.removeSync('/home/jprichardson') // I just deleted my entire HOME directory.
```

---

### Remove (`docs/remove.md`)

# remove(path[, callback])

Removes a file or directory. The directory can have contents. If the path does not exist, silently does nothing.

- `path` `<String>`
- `callback` `<Function>`
  - `err` `<Error>`

## Example:

```js
const fs = require('fs-extra')

// remove file
// With a callback:
fs.remove('/tmp/myfile', err => {
  if (err) return console.error(err)
  console.log('success!')
})

fs.remove('/home/jprichardson', err => {
  if (err) return console.error(err)
  console.log('success!') // I just deleted my entire HOME directory.
})

// With Promises:
fs.remove('/tmp/myfile')
.then(() => {
  console.log('success!')
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example (src, dest) {
  try {
    await fs.remove('/tmp/myfile')
    console.log('success!')
  } catch (err) {
    console.error(err)
  }
}

example()
```

---

### WriteJson Sync (`docs/writeJson-sync.md`)

# writeJsonSync(file, object[, options])

Writes an object to a JSON file.

**Alias:** `writeJSONSync()`

- `file` `<String>`
- `object` `<Object>`
- `options` `<Object>`
  - `spaces` `<Number> | <String>` Number of spaces to indent; or a string to use for indentation (i.e. pass `'\t'` for tab indentation). See [the docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#The_space_argument) for more info.
  - `EOL` `<String>` Set EOL character. Default is `\n`.
  - `replacer` [JSON replacer](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#The_replacer_parameter)
  - Also accepts [`fs.writeFileSync()` options](https://nodejs.org/api/fs.html#fs_fs_writefilesync_file_data_options)

## Example:

```js
const fs = require('fs-extra')

fs.writeJsonSync('./package.json', {name: 'fs-extra'})
```
---

**See also:** [`outputJsonSync()`](outputJson-sync.md)

---

### WriteJson (`docs/writeJson.md`)

# writeJson(file, object[, options][, callback])

Writes an object to a JSON file.

**Alias:** `writeJSON()`

- `file` `<String>`
- `object` `<Object>`
- `options` `<Object>`
  - `spaces` `<Number> | <String>` Number of spaces to indent; or a string to use for indentation (i.e. pass `'\t'` for tab indentation). See [the docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#The_space_argument) for more info.
  - `EOL` `<String>` Set EOL character. Default is `\n`.
  - `replacer` [JSON replacer](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#The_replacer_parameter)
  - Also accepts [`fs.writeFile()` options](https://nodejs.org/api/fs.html#fs_fs_writefile_file_data_options_callback)
- `callback` `<Function>`
  - `err` `<Error>`

## Example:

```js
const fs = require('fs-extra')

// With a callback:
fs.writeJson('./package.json', {name: 'fs-extra'}, err => {
  if (err) return console.error(err)
  console.log('success!')
})

// With Promises:
fs.writeJson('./package.json', {name: 'fs-extra'})
.then(() => {
  console.log('success!')
})
.catch(err => {
  console.error(err)
})

// With async/await:
async function example () {
  try {
    await fs.writeJson('./package.json', {name: 'fs-extra'})
    console.log('success!')
  } catch (err) {
    console.error(err)
  }
}

example()
```

---

**See also:** [`outputJson()`](outputJson.md)

---

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