Exnotify.add_watch

You're seeing just the function add_watch, go back to Exnotify module for more information.
Link to this function

add_watch(name, pathname, events \\ [:notify_in_create], opts \\ [])

Specs

add_watch(
  name :: GenServer.name(),
  pathname :: String.t(),
  events :: [
    :notify_in_access
    | :notify_in_attrib
    | :notify_in_close_write
    | :notify_in_close_nowrite
    | :notify_in_create
    | :notify_in_delete
    | :notify_in_delete_self
    | :notify_in_modify
    | :notify_in_moved_from
    | :notify_in_moved_to
    | :notify_in_open
    | :notify_in_move
  ],
  opts :: []
) :: :ok | {:error, any()}

Watch for events on directory or file.