Class FileHandle

constructor

• new FileHandle(context: V_Context, fd: number): FileHandle

  Parameters

  • context: V_Context
  • fd: number

  Returns FileHandle

Readonlyfd

[asyncDispose]

• "[asyncDispose]"(): Promise<void>

  Returns Promise<void>

appendFile

• appendFile(
      data: string | Uint8Array<ArrayBufferLike>,
      _options?: BufferEncoding | ObjectEncodingOptions & FlagAndOpenMode,
  ): Promise<void>

  Asynchronously append data to a file, creating the file if it does not exist. The underlying file will not be closed automatically. The FileHandle must have been opened for appending.

  Parameters

  • data: string | Uint8Array<ArrayBufferLike>

    The data to write. If something other than a Buffer or Uint8Array is provided, the value is coerced to a string.

  • _options: BufferEncoding | ObjectEncodingOptions & FlagAndOpenMode = {}

    Either the encoding for the file, or an object optionally specifying the encoding, file mode, and flag.

    • encoding defaults to 'utf8'.
    • mode defaults to 0o666.
    • flag defaults to 'a'.

  Returns Promise<void>

chmod

• chmod(mode: Mode): Promise<void>

  Asynchronous fchmod(2) - Change permissions of a file.

  Parameters

  • mode: Mode

    A file mode. If a string is passed, it is parsed as an octal integer.

  Returns Promise<void>

chown

• chown(uid: number, gid: number): Promise<void>

  Asynchronous fchown(2) - Change ownership of a file.

  Parameters

  • uid: number
  • gid: number

  Returns Promise<void>

close

• close(): Promise<void>

  Asynchronous close(2) - close a FileHandle.

  Returns Promise<void>

createReadStream

• createReadStream(options?: CreateReadStreamOptions): ReadStream

  Creates a stream for reading from the file.

  Parameters

  • options: CreateReadStreamOptions = {}

    Options for the readable stream

  Returns ReadStream

createWriteStream

• createWriteStream(options?: CreateWriteStreamOptions): WriteStream

  Creates a stream for writing to the file.

  Parameters

  • options: CreateWriteStreamOptions = {}

    Options for the writeable stream.

  Returns WriteStream

datasync

• datasync(): Promise<void>

  Asynchronous fdatasync(2) - synchronize a file's in-core state with storage device.

  Returns Promise<void>

read

• read<T extends ArrayBufferView<ArrayBufferLike>>(
      buffer: T,
      offset?: number,
      length?: number,
      position?: null | number,
  ): Promise<FileReadResult<T>>

  Asynchronously reads data from the file. The FileHandle must have been opened for reading.

  Type Parameters

  • T extends ArrayBufferView<ArrayBufferLike>

  Parameters

  • buffer: T

    The buffer that the data will be written to.

  • Optionaloffset: number

    The offset in the buffer at which to start writing.

  • Optionallength: number

    The number of bytes to read.

  • Optionalposition: null | number

    The offset from the beginning of the file from which data should be read. If null, data will be read from the current position.

  Returns Promise<FileReadResult<T>>

• read<T extends ArrayBufferView<ArrayBufferLike> = Buffer<ArrayBufferLike>>(
      buffer: T,
      options?: FileReadOptions<T>,
  ): Promise<FileReadResult<T>>

  Asynchronously reads data from the file. The FileHandle must have been opened for reading.

  Type Parameters

  • T extends ArrayBufferView<ArrayBufferLike> = Buffer<ArrayBufferLike>

  Parameters

  • buffer: T

    The buffer that the data will be written to.

  • Optionaloptions: FileReadOptions<T>

  Returns Promise<FileReadResult<T>>

• read<T extends ArrayBufferView<ArrayBufferLike> = Buffer<ArrayBufferLike>>(
      options?: FileReadOptions<T>,
  ): Promise<FileReadResult<T>>

  Asynchronously reads data from the file. The FileHandle must have been opened for reading.

  Type Parameters

  • T extends ArrayBufferView<ArrayBufferLike> = Buffer<ArrayBufferLike>

  Parameters

  • Optionaloptions: FileReadOptions<T>

  Returns Promise<FileReadResult<T>>

readableWebStream

• readableWebStream(
      options?: StreamOptions,
  ): ReadableStream<Uint8Array<ArrayBufferLike>>

  Read file data using a ReadableStream. The handle will not be closed automatically.

  Parameters

  • options: StreamOptions = {}

  Returns ReadableStream<Uint8Array<ArrayBufferLike>>

readFile

• readFile(
      options?: null | { encoding?: null } & Abortable,
  ): Promise<Buffer<ArrayBufferLike>>

  Asynchronously reads the entire contents of a file.

  If options is a string, then it specifies the encoding.

  The FileHandle has to support reading.

  If one or more filehandle.read() calls are made on a file handle and then a filehandle.readFile() call is made, the data will be read from the current position till the end of the file. It doesn't always read from the beginning of the file.

  Parameters

  • Optionaloptions: null | { encoding?: null } & Abortable

  Returns Promise<Buffer<ArrayBufferLike>>

  Fulfills upon a successful read with the contents of the file. If no encoding is specified (using options.encoding), the data is returned as a {Buffer} object. Otherwise, the data will be a string.

  Since

  v10.0.0

• readFile(
      options: BufferEncoding | { encoding: BufferEncoding } & Abortable,
  ): Promise<string>

  Asynchronously reads the entire contents of a file. The underlying file will not be closed automatically. The FileHandle must have been opened for reading.

  Parameters

  • options: BufferEncoding | { encoding: BufferEncoding } & Abortable

  Returns Promise<string>

• readFile(
      _options?: null | BufferEncoding | ObjectEncodingOptions & Abortable,
  ): Promise<string | Buffer<ArrayBufferLike>>

  Asynchronously reads the entire contents of a file. The underlying file will not be closed automatically. The FileHandle must have been opened for reading.

  Parameters

  • Optional_options: null | BufferEncoding | ObjectEncodingOptions & Abortable

  Returns Promise<string | Buffer<ArrayBufferLike>>

readLines

• readLines(options?: CreateReadStreamOptions): Interface

  Creates a readline Interface object that allows reading the file line by line

  Parameters

  • Optionaloptions: CreateReadStreamOptions

    Options for creating a read stream

  Returns Interface

  A readline interface for reading the file line by line

readv

• readv(
      buffers: ArrayBufferView<ArrayBufferLike>[],
      position?: number,
  ): Promise<ReadVResult>

  Asynchronous readv. Reads into multiple buffers.

  Parameters

  • buffers: ArrayBufferView<ArrayBufferLike>[]

    An array of Uint8Array buffers.

  • Optionalposition: number

    The position in the file where to begin reading.

  Returns Promise<ReadVResult>

  The number of bytes read.

stat

• stat(opts: BigIntOptions): Promise<BigIntStats>

  Asynchronous fstat(2) - Get file status.

  Parameters

  • opts: BigIntOptions

  Returns Promise<BigIntStats>

• stat(opts?: StatOptions & { bigint?: false }): Promise<Stats>

  Asynchronous fstat(2) - Get file status.

  Parameters

  • Optionalopts: StatOptions & { bigint?: false }

  Returns Promise<Stats>

sync

• sync(): Promise<void>

  Asynchronous fsync(2) - synchronize a file's in-core state with the underlying storage device.

  Returns Promise<void>

truncate

• truncate(length?: number): Promise<void>

  Asynchronous ftruncate(2) - Truncate a file to a specified length.

  Parameters

  • length: number = 0

    If not specified, defaults to 0.

  Returns Promise<void>

utimes

• utimes(atime: TimeLike, mtime: TimeLike): Promise<void>

  Asynchronously change file timestamps of the file.

  Parameters

  • atime: TimeLike

    The last access time. If a string is provided, it will be coerced to number.

  • mtime: TimeLike

    The last modified time. If a string is provided, it will be coerced to number.

  Returns Promise<void>

writableWebStream

• writableWebStream(options?: StreamOptions): WritableStream
  Internal

  Not part of the Node.js API!

  Write file data using a WritableStream. The handle will not be closed automatically.

  Parameters

  • options: StreamOptions = {}

  Returns WritableStream

write

• write<T extends FileContents>(
      data: T,
      options?:
          | null
          | number
          | { length?: number; offset?: number; position?: number },
      lenOrEnc?: null | number | BufferEncoding,
      position?: null | number,
  ): Promise<{ buffer: T; bytesWritten: number }>

  Asynchronously writes string to the file. The FileHandle must have been opened for writing. It is unsafe to call write() multiple times on the same file without waiting for the Promise to be resolved (or rejected). For this scenario, createWriteStream is strongly recommended.

  Type Parameters

  • T extends FileContents

  Parameters

  • data: T
  • Optionaloptions: null | number | { length?: number; offset?: number; position?: number }
  • OptionallenOrEnc: null | number | BufferEncoding
  • Optionalposition: null | number

  Returns Promise<{ buffer: T; bytesWritten: number }>

writeFile

• writeFile(
      data: string | Uint8Array<ArrayBufferLike>,
      _options?: WriteFileOptions,
  ): Promise<void>

  Asynchronously writes data to a file, replacing the file if it already exists. The underlying file will not be closed automatically. The FileHandle must have been opened for writing. It is unsafe to call writeFile() multiple times on the same file without waiting for the Promise to be resolved (or rejected).

  Parameters

  • data: string | Uint8Array<ArrayBufferLike>

    The data to write. If something other than a Buffer or Uint8Array is provided, the value is coerced to a string.

  • _options: WriteFileOptions = {}

    Either the encoding for the file, or an object optionally specifying the encoding, file mode, and flag.

    • encoding defaults to 'utf8'.
    • mode defaults to 0o666.
    • flag defaults to 'w'.

  Returns Promise<void>

writev

• writev(
      buffers: Uint8Array<ArrayBufferLike>[],
      position?: number,
  ): Promise<WriteVResult>

  Asynchronous writev. Writes from multiple buffers.

  Parameters

  • buffers: Uint8Array<ArrayBufferLike>[]

    An array of Uint8Array buffers.

  • Optionalposition: number

    The position in the file where to begin writing.

  Returns Promise<WriteVResult>

  The number of bytes written.