title: C changing user
body: <p>Alright so my question is simple but I'm kinda new to C and I was hoping someone could help me. I want to change to a different user in C. For example, I know the user's password, and if the user types:
  ./change user1
  It will change to user1. I know this may be a security issue right now, but I'm not worried about security at the moment.</p>