Documentation for "User" option specifies wrong kind of argument
https://www.torproject.org/docs/tor-manual.html.en
User UID On startup, setuid to this user and setgid to their primary group.
A UID is an integer in unix speak, not a username. The description of the value uses "uid" correctly in the function names, but the option should say "username" because that is the only value it supports.
Trac:
Username: chadmiller