Node.js File System Complete Reference

Node.js File System module is used to handle file operations like creating, reading, deleting, etc. Node.js provides an inbuilt module called FS (File System). Node.js gives the functionality of file I/O by providing wrappers around the standard POSIX functions. All file system operations can have synchronous and asynchronous forms depending upon user requirements

Example:

Javascript

<script>
    // Node.js program to demonstrate the
    // fsPromises.opendir() method

    // Import the filesystem module
    const fs = require('fs');
    const fsPromises = fs.promises;

    fsPromises.opendir(__dirname)
        .then(function(result) {
            console.log(result);
        })
        .catch(function(error) {
            console.log(error);
        });
</script>

Output:

Dir {
  [Symbol(kDirHandle)]: DirHandle {},
  [Symbol(kDirBufferedEntries)]: [],
  [Symbol(kDirPath)]: 'C:\\Users\\Lenovo\\Downloads\\Internship\\Program',
  [Symbol(kDirClosed)]: false,
  [Symbol(kDirOptions)]: { bufferSize: 32, encoding: 'utf8' },
  [Symbol(kDirReadPromisified)]: [Function: bound [kDirReadImpl]],
  [Symbol(kDirClosePromisified)]: [Function: bound close]
}

The Complete NodeJS File System are listed below:

Node.js File System	Description
Node.js fs.readFile() Method	This method read the entire file into buffer. To load the fs module we use require() method.
Node.js fs.exists() Method	The fs.exists() method is used to test whether the given path exists or not in the file system.
Node.js fs.existsSync() Method	The fs.existsSync() method is used to synchronously check if a file already exists in the given path or not.
Node.js fs.mkdir() Method	The fs.mkdir() method i Node.js is used to create a directory asynchronously.
Node.js fs.truncate() Method	The fs.truncate() method in node.js is used to change the size of the file i.e either increase or decrease the file size.
Node.js fs.renameSync() Method	The fs.renameSync() method is used to synchronously rename a file at the given old path to the given new path.
Node.js fs.rmdir() Method	The fs.rmdir() method is used to delete a directory at the given path.
Node.js fs.stat() Method	The fs.stat() method is used to return information about the given file or directory.
Node.js fs.mkdtempSync() Method	The fs.mkdtempSync() method is an inbuilt application programming interface of fs module
Node.js fs.realpath() Method	The fs.realPath() method is used to compute the canonical pathname of the given path.
Node.js fs.open() Method	This is used. fs.readFile() is only for reading the file and similarly fs.writeFile()
Node.js fs.mkdirSync() Method	This is an inbuilt application programming interface of fs module which provides an API for interacting with the file system in a manner closely modeled around standard POSIX functions.
Node.js fs.statSync() Method	The fs.statSync() method is used to synchronously return information about the given file path.
Node.js fs.write() Method	The fs.write() method is an inbuilt application programming interface of fs module which is used to specify the position
Node.js fs.createReadStream() Method	This is an inbuilt application programming interface of fs module which allow you to open up a file/stream and read the data present in it.
Node.js fs.openSync() Method	This is an inbuilt application programming interface of fs module which is used to return an integer value that represents the file descriptor.
Node.js fs.rmdirSync() Method	The fs.rmdirSync() method is used to synchronously delete a directory at the given path.
Node.js fs.ftruncate() Method	The fs.ftruncate() method is used to change the size of the file i.e. either increase or decrease the file size.
Node.js fs.truncateSync() Method	The fs.truncateSync() method is used to synchronously change the size of the file
Node.js fs.readdir() Method	The fs.readdir() method is used to asynchronously read the contents of a given directory.
Node.js fs.writeFileSync() Method	The ‘fs’ module of Node.js implements the File I/O operation. Methods in the fs module can be synchronous as well as asynchronous.
Node.js fs.readFileSync() Method	The fs.readFileSync() method is an inbuilt application programming interface of fs module which is used to read the file and return its content.
Node.js fs.lstat() Method	The fs.lstat() method is similar to the fs.stat() method except that it is used to return
Node.js fs.symlinkSync() Method	The fs.symlinkSync() method is used to synchronously create a symlink to the specified path.
Node.js fs.realpathSync() Method	The fs.realpathSync() method is used to synchronously compute the canonical pathname of a given path.
Node.js fs.fstat() Method	The fs.fstat() method is used to return information about the given file descriptor.
Node.js fs.mkdtemp() Method	The fs.mkdtemp() method is used to create a unique temporary directory.
Node.js fs.lstatSync() Method	This  is used to synchronously return information about the symbolic link that is being used to refer to a file or directory.
Node.js fs.readdirSync() Me thod	This is used to synchronously read the contents of a given directory.
Node.js fs.writeFile() Method	The fs.writeFile() method is used to asynchronously write the specified data to a file.
Node.js fs.fstatSync() Method	The fs.fstatSync() method is used to synchronously return information about the given file descriptor.
Node.js fs.copyFileSync() Function	This  is used to synchronously copy a file from the source path to destination path.
Node.js fs. lchown() Method	fs.chownSync() method which does dereference the links to their path.
Node.js fs. lchownSync() Method	fs.chownSync() method which does dereference the links to their path.
Node.js fs.closeSync() Method	fs.closeSync() on a file descriptor while some other operation is being performed on it may lead to undefined behavior.
Node.js fs.close() Method	This is used to asynchronously close the given file descriptor thereby clearing the file that is associated with it.
Node.js fs.fchmod() Method	The fs.fchmod() method is used to change the permissions of a given file descriptor.
Node.js fs.link() Method	The fs.link() method is used to create a hard link to the given path.
Node.js fs.symlink() Function	The fs.symlink() method is used to create a symlink to the specified path.
Node.js fs.unlinkSync() Method	The fs.unlinkSync() method is used to synchronously remove a file or symbolic link from the filesystem.
Node.js fs.chmodSync() Method	The fs.chmodSync() method is used to synchronously change the permissions of a given path.
Node.js fs.chmod() Method	These permissions can be specified using string constants or octal numbers that correspond to their respective file modes.
Node.js fs.unlink() Method	The fs.unlink() method is used to remove a file or symbolic link from the filesystem.
Node.js fs.fchmodSync() Method	The fs.fchmodSync() method is an inbuilt application programming of fs module which is used to synchronously change the permissions of a given file descriptor.
Node.js fs.readlinkSync() Method	This  is used to synchronously return a symbolic link’s value, i.e. the path it is linked to.
Node.js fs. linksync() Method	The hard link created would still point to the same file even if the file is renamed.
Node.js fs.futimesSync() Method	This is used to synchronously change the modification and access timestamps of given file descriptor. T
Node.js fs.utimesSync() Method	The fs.utimesSync() method is used to synchronously change the modification and access timestamps of a file.
Node.js fs.utimes() Method	The fs.utimes() method is used to asynchronously change the modification and access timestamps of a file.
Node.js fs.opendirSync() Method	The fs.opendirSync() method is used to synchronously open a directory in the file system.
Node.js fs.opendir() Method	It creates an fs.Dir object that is used to represent the directory.
Node.js fs.appendFile() Function	The fs.appendFile() method is used to asynchronously append the given data to a file. A new file is created if it does not exist.
Node.js fs.chown() Method	The fs.chown() method is used to asynchronously change the owner and group of the given path.
Node.js fs.fchown() Function	The fs.fchown() method is used to change the owner and group of the given file descriptor.
Node.js fs.copyFile() Function	The fs.copyFile() method is used to asynchronously copy a file from the source path to destination path.
Node.js fs.appendFileSync() Function	A new file is created if it does not exist. The optional options parameter can be used to modify the behavior of the operation.
Node.js fs. fchownSync() Method	The function accepts a user id and group id that can be used to set the respective owner and group. It does not return anything.
Node.js fs.chownSync() Method	The fs.chownSync() method is used to synchronously change the owner and group of the given path.
Node.js fs.accessSync() Method	The fs.accessSync() method is used to synchronously test the permissions of a given file or directory.
Node.js fs.access() Method	The permissions to be checked can be specified as a parameter using file access constants.
Node.js fs.watchFile() Method	The fs.watchFile() method is used to continuously watch for changes on the given file.
Node.js fsPromises.mkdtemp() Method	The fsPromises.mkdtemp() method is an inbuilt method which creates a unique temporary directory and resolves the Promise with the created directory path.
Node.js fsPromises.chmod() Method	The fsPromises.chmod() method is used to change the permissions of a given path.
Node.js fs.unwatchFile() Method	The fs.unwatchFile() method is used to stop watching for changes on the given file.
Node.js fsPromises.open() Method	The fsPromises.open() method is used to asynchronously open a file that returns a Promise that, when resolved, yields a FileHandle object.
Node.js fsPromises.mkdir() Method	This is used to asynchronously create a directory then resolves the Promise with either no arguments, or the first directory path created if recursive is true.
Node.js fs.promise.readdir() Method	The fs.promise.readdir() method defined in the File System module of Node.js.
Node.js fsPromises.appendFile() Function	The fsPromises.appendFile() method is used to asynchronously append the given data to a file.
Node.js fsPromise.lstat() Method	The fs.promise.lstat() method is defined in the File System module of Node.js.
Node.js fsPromises.stat() Method	The fsPromises.stat() method is used to return information about the given file or directory.
Node.js fsPromises.realpath() Method	The fsPromises.realPath() method determines the actual location of path using the same semantics as the fs.realpath.native() function
Node.js fs.read() Method	Node.js is used for server-side scripting. Reading and writing files are the two most important operations that are performed in any application.
Node.js fsPromises.chown() Method	The fsPromises.chown() method is used to change the ownership of a file then resolves the Promise with no arguments upon success.
Node.js fs.createWriteStream() Method	This is an inbuilt application programming interface of fs module which allows to quickly make a writable stream for the purpose of writing data to a file.
Node.js fs.futimes() Method	The fs.futimes() method is used to asynchronously change the modification and access timestamps of given file descriptor.
Node.js fsPromises.truncate() Method	The fsPromises.truncate() method is defined in the File System module of Node.js.
Node.js fsPromises.symlink() Method	The fsPromises.symlink() method is used to create a symlink to the specified path then resolves the Promise with no arguments upon success.
Node.js fsPromises.lchmod() Method	The fsPromises.lchmod() method is used to change the permissions of a given path.
Node.js fsPromises.lchown() Method	The fsPromises.lchown() method is used to change the ownership of a file then resolves the Promise with no arguments upon success
Node.js fsPromises.truncate() Method	The fsPromises.truncate() method in node.js is used to change the size of the file i.e. either increase or decrease the file size.
Node.js fsPromises.opendir() Method	The fsPromises.opendir() method is used to asynchronously open a directory in the file system.
Node.js fsPromises.utimes() Method	The fsPromises.utimes() method is used to asynchronously change the modification and access timestamps of a file.
Node.js fsPromises.copyFile() Method	The fsPromises.copyFile() method is used to asynchronously copy a file from the source path to destination path.
Node.js fsPromises.rename() Method	The fsPromises.rename() method is used to asynchronously rename a file at the given old path to a given new path.
Node.js fs.promises.appendFile() Method	The fs.promises.appendFile() method of File System module in Node.js is used to interact with the hard disk of the user’s computer.
Node.js fsPromises.rmdir() Method	The fsPromises.rmdir() method is used to delete a directory at the given path. It can also be used recursively to remove nested directories.
Node.js fsPromises.writeFile() Method	The fsPromises.writeFile() method is used to asynchronously write the specified data to a file. By default, the file would be replaced if it exists.
Node.js fsPromises.readFile() Method	The fsPromises.readFile() method is used to read the file. This method read the entire file into buffer.
Node.js fsPromises.access() Method	The fsPromises.access() method is used to test the permissions of a given file or directory specified by path.
Node.js stats.ino Property	The stats.ino property is an inbuilt application programming interface of the fs.Stats class is used to get the “Inode” number of the file specified by the file system.
Node.js stats.birthtimeNs Property	This is an inbuilt application programming interface of the fs.Stats class is used to get the timestamp when the file is created since the POSIX epoch expressed in milliseconds.
Node.js stats.atimeNs Property	This is  an inbuilt application programming interface of the fs.Stats class is used to get the timestamp when the file is accessed last time since the POSIX epoch expressed in nanoseconds.
Node.js fsPromises.opendir() Method	The File System module is basically to interact with the hard disk of the user’s computer. The method is used to asynchronously open a directory.
Node.js stats.mtimeNs Property	The stats.mtimeNs property is an inbuilt application programming interface of the fs.
Node.js stats.isFIFO() Method	This  is an inbuilt application programming interface of the fs.Stats class which is used to check whether fs.Stats object describes a first-in-first-out (FIFO) pipe or not.
Node.js stats.isSymbolicLink() Method	This is an inbuilt application programming interface of the fs.Stats class which is used to check whether fs.Stats object describes a symbolic link or not.
Node.js stat.isSocket() Method	The stats.isSocket() method is an inbuilt application programming interface of the fs.
Node.js stats.dev Property	The stats.dev property is an inbuilt application programming interface of the fs.
Node.js stats.mtime Property	The stats.mtime property is an inbuilt application programming interface of the fs.Stats class is used to get the timestamp when the file is modified last time.
Node.js filehandle.readFile() Method	The filehandle.readFile() method is used to asynchronously read the file contents. This method reads the entire file into the buffer. It Asynchronously reads the entire contents of a file.
Node.js stats.ctimeNs Property	The stats.ctimeNs property is an inbuilt application programming interface of the fs.
Node.js stats.atime Property	This used to get the time and date when the file is accessed last time.
Node.js stats.birthtime Property	This is used to get the timestamp when the file is created.
Node.js stats.ctime Property	The stats.ctime property is an inbuilt application programming interface of the fs.
Node.js stats.ctimeMs Property from fs.Stats Class	The stats.ctimeMs property is an inbuilt application programming interface of the fs.
Node.js stats.mtimeMs Property from fs.Stats Class	The stats.mtimeMs property is an inbuilt application programming interface of the fs.Stats class is used to get the timestamp
Node.js stats.blocks Property from fs.Stats Class	The stats.blocks property is an inbuilt application programming interface of the fs.Stats class is used to get the number of blocks allocated for the file.
Node.js stats.isCharacterDevice() Method from fs.Stats Class	The stats.isCharacterDevice() method is an inbuilt application programming interface of the fs.Stats class which is used to check whether fs.Stats object is of a character device or not.
Node.js stats.atimeMs Property from fs.Stats Class	The stats.atimeMs property is an inbuilt application programming interface of the fs.Stats class is used to get the timestamp
Node.js stats.birthtimeMs Property from fs.Stats Class	This is used to get the timestamp when the file is created since the POSIX epoch expressed in milliseconds.
Node.js filehandle.stat() Method from class: FileHandle	The File System module is basically to interact with the hard disk of the user’s computers.
Node.js stats.blksize Property from fs.Stats Class	The stats.blksize property is an inbuilt application programming interface of the fs.Stats class is used to get the block size for I/O operations in the file system in bytes.
Node.js stats.size Property from fs.Stats Class	The stats.size property is an inbuilt application programming interface of the fs.Stats class is used to get the size of the file in bytes.
Node.js stats.nlink Property from fs.Stats Class	The stats.nlink property is an inbuilt application programming interface of the fs.Stats class which is used to get the number of hard-links for the file.
Node.js stats.mode Property from fs.Stats Class	The stats.mode property is an inbuilt application programming interface of the fs.Stats class which is used to get the file type and mode as bit-field.
Node.js stats.isFile() Method from fs.Stats Class	The stats.isFile() method is an inbuilt application programming interface of the fs.Stats class which is used to check whether fs.Stats object describes a file or not.
Node.js stats.gid Property from fs.Stats Class	This is used to get the numeric (number / bigint) identity of the group to which the file belongs to.
Node.js stats.uid Property from fs.Stats Class	The stats.uid property is an inbuilt application programming interface of the fs.Stats class is used to get the numeric (number / bigint) identity of the user to which the file belongs to.
Node.js stats.rdev Property from fs.Stats Class	This  is used to get the numeric (number / bigint) identity of the device in which the file is stored in the file is considered to be “special”.
Node.js fs.filehandle.utimes() Method	The fs.filehandle.utimes() method is an inbuilt application programming interface of class fs.filehandle within File System
Node.js fs.filehandle.truncate() Method	This is used to truncate the particular file object and only that much byte will be retained which passed as an integer in truncate() method.
Node.js fs.Dirent.isFIFO() Method	This is used to check if the particular dirent describes a first in first out pipe or not.
Node.js fs.filehandle.fd() Method	This is used to provide the numeric file descriptor of this file handle object.
Node.js fs.Dirent.isSocket() Method	This is used to check if the particular dirent describes a Socket or not.
Node.js fs.Dirent.isFile() Method	This is used to check if the particular dirent describes a File or not.
Node.js fs.filehandle.write() Method	This is an inbuilt application programming interface of class fs.filehandle within File System module which is used to write the data form the buffer to that particular file.
Node.js fs.Dir.close() Method	This  is used to close the directory’s underlying resource handle asynchronously.
Node.js fs.Dirent.isCharacterDevice() Method	This is used to check if the particular dirent describes a character device or not.
Node.js fs.Dir.read() Method	This is used to read the each next directory (dirent) one by one asynchronously.
Node.js fs.Dirent.isBlockDevice() Method	This is used to check if the particular dirent describes a block device or not.
Node.js filehandle.close() Method	This is used to asynchronously close the given file descriptor thereby clearing the file that is associated with it.
Node.js filehandle.read() Method	In order to read files without file descriptor the readFile() method of the filehandle package can be used.
Node.js stats.isDirectory() Method from fs.Stats Class	This is used to check whether fs.Stats object describes a file system directory or not.
Node.js filehandle.writeFile() Method from class: FileHandle	This is used to defined in the File System module of Node.js. The File System module is basically to interact with the hard disk of the user’s computer.
Node.js fs.Dir.path() Method	This is used to defined in the File System module of Node.js. The File System module is basically to interact with the hard disk of the user’s computer.
Node.js fs.filehandle.datasync() Method	fs.filehandle within File System module which is used to sync the data of the file.
Node.js fs.filehandle.chmod() Method	fs.filehandle within File System module which is used to change the permission of the particular file.
Node.js stats.isBlockDevice() Method from fs.Stats Class	This  is used to check whether fs.Stats object is of a block device or not.
Node.js fs.filehandle.chown() Method	This is used to change the ownership of the particular file.
Node.js fs.filehandle.sync() Method	fs.filehandle within File System module which is used to synchronize this file’s in-core state with the storage device.
Node.js filehandle.truncate() Method	The truncate() method used to modify the inner contents of the file by ‘len’ bytes.
Node.js fs.dirent.name Property	The fs.Dirent.name property is an inbuilt application programming interface of class fs.Dirent
Node.js filehandle.appendFile() Method	The File System module is basically to interact with the hard disk of the user’s computer.
Node.js fs.Dirent.isDirectory() Method	This is used to check if the particular dirent describes a Directory or not.
Node.js fs.Dirent.isSymbolicLink() Method	This is used to check if the particular dirent describes a SymbolicLink or not.
Node.js fs.Dir.readSync() Method	fs.Dir within File System module which is used to read the each next dirent of directory.
Node.js fs.Dir.closeSync() Method	This is used to close the directory’s underlying resource handle synchronously.
Node.js fs.promises.link() Method	The fs.promises.link() method is an inbuilt application programming interface of the fs.promises class which is used to make a new name for a file.
Node.js fs.watch() Method	fs module which is used to continuously watch for changes in the given file or directory.
Node.js fs.readlink() Method	The fs.readlink() method is an inbuilt application programming interface of fs module which is used to asynchronously return a symbolic link’s value.
Node.js fs.fdatasync() Method	The fs.fdatasync() (Added in v0.1.96) method is an inbuilt application programming interface of the fs module which is similar to fs.fsync()
Node.js fs.fsync() Method	It has both synchronous and asynchronous forms. The asynchronous form always takes a completion callback as its last argument.
Node.js fs.rmSync() Method	The fs.rmSync() method is used to synchronously delete a file at the given path.
Node.js fs.rm() Method	The fs.rm() method is used to delete a file at the given path. It can also be used recursively to remove directories.
Node.js fs.writeSync() Method	This is used to work with files on the computer. The functions of the module can be used by importing the fs module.