kotlin-node/node.fs/appendFile

appendFile

external fun appendFile(path: PathOrFileDescriptor, data: String, options: WriteFileOptions, callback: NoParamCallback)(source)

external fun appendFile(path: PathOrFileDescriptor, data: Uint8Array<*>, options: WriteFileOptions, callback: NoParamCallback)(source)

Asynchronously append data to a file, creating the file if it does not yet exist. data can be a string or a Buffer.

The mode option only affects the newly created file. See {@link open} for more details.

import { appendFile } from 'node:fs';

appendFile('message.txt', 'data to append', (err) => {
  if (err) throw err;
  console.log('The "data to append" was appended to file!');
});

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

import { appendFile } from 'node:fs';

appendFile('message.txt', 'data to append', 'utf8', callback);

The path may be specified as a numeric file descriptor that has been opened for appending (using fs.open() or fs.openSync()). The file descriptor will not be closed automatically.

import { open, close, appendFile } from 'node:fs';

function closeFd(fd) {
  close(fd, (err) => {
    if (err) throw err;
  });
}

open('message.txt', 'a', (err, fd) => {
  if (err) throw err;

  try {
    appendFile(fd, 'data to append', 'utf8', (err) => {
      closeFd(fd);
      if (err) throw err;
    });
  } catch (err) {
    closeFd(fd);
    throw err;
  }
});

Since

v0.6.7

Parameters

path

filename or file descriptor

external fun appendFile(file: PathOrFileDescriptor, data: String, callback: NoParamCallback)(source)

external fun appendFile(file: PathOrFileDescriptor, data: Uint8Array<*>, callback: NoParamCallback)(source)

Asynchronously append data to a file, creating the file if it does not exist.

Parameters

file

A path to a file. If a URL is provided, it must use the file: protocol. If a file descriptor is provided, the underlying file will not be closed automatically.

data

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

suspend external fun appendFile(path: PathLike, data: String): Void(source)

suspend external fun appendFile(path: PathLike, data: String, options: AppendFileAsyncOptions? = definedExternally): Void(source)

suspend external fun appendFile(path: PathLike, data: String, options: BufferEncoding? = definedExternally): Void(source)

suspend external fun appendFile(path: PathLike, data: Uint8Array<*>): Void(source)

suspend external fun appendFile(path: PathLike, data: Uint8Array<*>, options: AppendFileAsyncOptions? = definedExternally): Void(source)

suspend external fun appendFile(path: PathLike, data: Uint8Array<*>, options: BufferEncoding? = definedExternally): Void(source)

suspend external fun appendFile(path: FileHandle, data: String): Void(source)

suspend external fun appendFile(path: FileHandle, data: String, options: AppendFileAsyncOptions? = definedExternally): Void(source)

suspend external fun appendFile(path: FileHandle, data: String, options: BufferEncoding? = definedExternally): Void(source)

suspend external fun appendFile(path: FileHandle, data: Uint8Array<*>): Void(source)

suspend external fun appendFile(path: FileHandle, data: Uint8Array<*>, options: AppendFileAsyncOptions? = definedExternally): Void(source)

suspend external fun appendFile(path: FileHandle, data: Uint8Array<*>, options: BufferEncoding? = definedExternally): Void(source)

Asynchronously append data to a file, creating the file if it does not yet exist. data can be a string or a Buffer.

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

The mode option only affects the newly created file. See fs.open() for more details.

The path may be specified as a FileHandle that has been opened for appending (using fsPromises.open()).

Since

v10.0.0

Return

Fulfills with undefined upon success.

Parameters

path

filename or {FileHandle}