Node fs.promises.watch function | API Reference

function watch(

options: 'buffer' | WatchOptions & { encoding: 'buffer' }

): AsyncIterable<FileChangeInfo<Buffer<ArrayBufferLike>>>;

Returns an async iterator that watches for changes on filename, where filenameis either a file or a directory.

import { watch } from 'node:fs/promises';

const ac = new AbortController();
const { signal } = ac;
setTimeout(() => ac.abort(), 10000);

(async () => {
  try {
    const watcher = watch(__filename, { signal });
    for await (const event of watcher)
      console.log(event);
  } catch (err) {
    if (err.name === 'AbortError')
      return;
    throw err;
  }
})();

On most platforms, 'rename' is emitted whenever a filename appears or disappears in the directory.

All the caveats for fs.watch() also apply to fsPromises.watch().

@returns

of objects with the properties:

function watch(

filename: PathLike,

options?: BufferEncoding | WatchOptions

): AsyncIterable<FileChangeInfo<string>>;

Watch for changes on filename, where filename is either a file or a directory, returning an FSWatcher.

@param filename

A path to a file or directory. If a URL is provided, it must use the file: protocol.

@param options

Either the encoding for the filename provided to the listener, or an object optionally specifying encoding, persistent, and recursive options. If encoding is not supplied, the default of 'utf8' is used. If persistent is not supplied, the default of true is used. If recursive is not supplied, the default of false is used.

function watch(

filename: PathLike,

options: string | WatchOptions

): AsyncIterable<FileChangeInfo<Buffer<ArrayBufferLike>>, any, any> | AsyncIterable<FileChangeInfo<string>, any, any>;

Watch for changes on filename, where filename is either a file or a directory, returning an FSWatcher.

@param filename

A path to a file or directory. If a URL is provided, it must use the file: protocol.

@param options

Either the encoding for the filename provided to the listener, or an object optionally specifying encoding, persistent, and recursive options. If encoding is not supplied, the default of 'utf8' is used. If persistent is not supplied, the default of true is used. If recursive is not supplied, the default of false is used.