gulp.watch - Error: watch null EMFILE

gulp.watch is giving an error in the simplest use-case that I’ve set up. I’ve been using gulp.watch in a few projects and this error is “all-of-a-sudden”. Perhaps I’m overlooking something? Are my glasses on my face but I can’t find them?

Here is my gulpfile.js contents:

var gulp = require('gulp');
var less = require('gulp-less');

gulp.task('default', function() {
  gulp.watch('styles.less', ['styles']);
});

gulp.task('styles', function() {
  return gulp.src('styles.less')
  .pipe(less())
  .pipe(gulp.dest(''));
});

As you can see, this is a simple scenario where watching a less file change will result in compiling that file to css. Here’s what I see in the console when I run ‘gulp’:

[19:19:30] Using gulpfile ~/Projects/Sandbox/fred/gulpfile.js
[19:19:30] Starting 'default'...
2016-01-23 19:19 gulp[41595] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-21)
[19:19:30] Finished 'default' after 7.91 ms
events.js:141
  throw er; // Unhandled 'error' event
  ^

Error: watch null EMFILE
  at exports._errnoException (util.js:856:11)
  at FSEvent.FSWatcher._handle.onchange (fs.js:1296:21)

I also tried replacing the contents of the ‘styles’ task to just contain a console.log statement. Same results. Any thoughts on this?

[lichenbuliren]

I have the same problem with you . finally i found that the actually problem is that if you open you project directory with command sublime . under terminal，and then run the gulp, that the gulp will cause the error.

so, you can open sublime application first, and then load you project directory, and finally start gulp in the terminal. everything will be ok！

hope this will help you

[qodesmith]

I only have Sublime, the terminal, and Chrome open at the same time (nothing novel here). What I did notice is that if I close sublime and then run gulp, the process runs with no error. So damn weird. And to add to the weirdness, this error is not consistent. My life.