Since LinkedIn discontinued their network updates RSS feeds, I haven't been able to find any "simple" mechanism to gain access to update feeds w/o going through the oauth process requiring the user to authenticate first. The few examples I've seen posted here all assume you've obtained the auth token first. Is that even possible?
In case anyone else inquires: https://developer.linkedin.com/support/faq
If your application requires you to make API calls in an automated way - without user interaction, you need to bootstrap the first access token request by manually signing in, and then ensure that your application refreshes the token automatically prior to expiry to avoid the need for additional human authentication.