# Fix 'EMFILE: too many open files, watch' in React Native

> Learn how to fix the EMFILE too many open files watch error in React Native on macOS by installing the watchman utility with Homebrew.

Author: [Flavio Copes](https://flaviocopes.com/about/) | Published: 2020-10-22 | Canonical: https://flaviocopes.com/react-native-emfile-too-many-open-files/

I was starting a [React](https://flaviocopes.com/react/) Native project on my MacBook Air but when running the command:

```bash
npx react-native start
```

I got an error that contained this line:

```
Error: EMFILE: too many open files, watch
```

I tried various ways to solve, until I found the suggestion to install the `watchman` utility using [Homebrew](https://flaviocopes.com/homebrew/).

I ran

```bash
brew install watchman
```

and that fixed the problem, because React Native internally was able to use `watchman` to watch files changes (used to provide hot reloading in the app to refresh it when a file is changed).

`watchman` looks like it's more efficient than the built-in files watch system, since I got rid of that error.