====== inotify ======
With ''inotify'', you can efficiently watch your filesystem for changes and run commands based on the results.

===== Limits =====

You can get your current inotify file watch limit by executing:

<code bash>$ cat /proc/sys/fs/inotify/max_user_watches</code>

You may need to increase the number of files one user can watch with inotify. Many distributions have a default limit of 8192 watched files per user. The maximum amount is 524288. You can set a new limit temporary with:

<code bash>
$ sudo sysctl fs.inotify.max_user_watches=524288
$ sudo sysctl -p
</code>

To make it permanent, store it in the ''sysctl'' config file.

<file - /etc/sysctl.d/40-max-user-watches.conf>
fs.inotify.max_user_watches=524288
</file>

On Arch Linux, Fedora and other RPM-based distributions, you apply this with ''sudo sysctl --system''. On Debian, Ubuntu and many other systems, this has to be in /etc/sysctl.conf and you apply it with ''sudo sysctl -p''.

You may also need to pay attention to the values of ''fs.inotify.max_queued_events'' and ''fs.inotify.max_user_instances'' if watching is slow or hangs.

([[https://github.com/guard/listen/wiki/Increasing-the-amount-of-inotify-watchers|source]])

===== Programs using inotify =====
Non-exhaustive list of programs which use inotify to watch for changes and may have problems with restrictive limits:

  * [[:admin:cloud:syncthing|Syncthing]]
  * [[dev:ide:vscode|Visual Studio Code]]