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node-watch Status

A wrapper and enhancements for (with 0 dependencies).



npm install node-watch


var watch = require('node-watch');
watch('file_or_dir', { recursive: true }, function(evt, name) {
  console.log('%s changed.', name);

This is a completely rewritten version, much faster and in a more memory-efficient way. So with recent nodejs under OS X or Windows you can do something like this:

// watch the whole disk 
watch('/', { recursive: true }, console.log);


  • Some editors will generate temporary files which will cause the callback function to be triggered multiple times.
  • When watching a single file the callback function will only be triggered once.
  • Missing an option to watch a directory recursively.
  • Recursive watch is not supported on Linux or in older versions of nodejs.


The events provided by the callback function is either update or remove, which is less confusing to's rename and change.

watch('./', function(evt, name) {
  if (evt == 'update') {
    // on create or modify 
  if (evt == 'remove') {
    // on delete 


The usage and options of node-watch is fully compatible with

  • persistent: <Boolean> default = true
  • recursive: <Boolean> default = false
  • encoding: <String> default = 'utf8'
Extra options
  • filter: <RegExp | Function> filter using regular expression or custom function.
// watch only for json files 
watch('./', { filter: /\.json$/ }, console.log);
// ignore node_modules 
watch('./', {
  recursive: true,
  filter: function(name) {
    return !/node_modules/.test(name);
}, console.log);

Watcher object

The watch function returns a fs.FSWatcher like object as the same as (>= v0.4.0).

var watcher = watch('./', { recursive: true });
watcher.on('change', function(evt, name) {
  // callback 
watcher.on('error', function(err) {
  // handle error 
// close 
// is closed? 

The watcher object is also an instance of EventEmitter. This's a list of methods for watcher specifically:

  • .on
  • .once
  • .emit
  • .close
  • .listeners
  • .setMaxListeners
  • .getMaxListeners
Extra methods
  • .isClosed detect if the watcher is closed

Known issues

Windows, node < v4.2.5

  • Failed to detect remove event
  • Failed to get deleted filename or directory name


1. Watch multiple files or directories in one place

watch(['file1', 'file2'], console.log);

2. Customize watch command line tool

#!/usr/bin/env node
var watcher = require('node-watch')(
  process.argv[2] || './', { recursive: true }, console.log
process.on('SIGINT', watcher.close);

Monitoring chrome from disk:

$ watch / | grep -i chrome



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