sorry to jump on this.
I have the same question.
We want have some public information with a link where a unknown user can access a course.
This courses save some data to the user so it must be a moodle user.
I can create a user by webservices and enroll it to the course.
But how can I login this user without showing the login screen?
Can I use a one-time-login-link?
Or pass username and password via get to the login link?