Current State

If :INotify::Notifier.new (or #watch) were to raise Errno::ENOSPC, the linux driver would abort the containing process:

      def _configure(directory, &callback)
        require 'rb-inotify'
        @worker ||= ::INotify::Notifier.new
        @worker.watch(directory.to_s, *options.events, &callback)
      rescue Errno::ENOSPC
        abort(INOTIFY_LIMIT_MESSAGE)
      end

Calling abort from a gem is never appropriate.

Desired State

Errno::ENOSPC should be wrapped by raising a named exception (with ENOSPC as the cause). That will raise out of the public interface start. The calling code in the containing process can then take the appropriate action, by rescuing that specific exception or a catch-all base class.

Steps to Reproduce

I didn't try, but you'd need to run out the count of inotify file descriptors. Then call listener.start. That would cause the containing process to abruptly abort.