Hey.
Man page of logname say:
"Print the name of the current user."
IMO that's ambiguous as it's probably ought to be the name returned by
getlogin().
So when I login as normal user, and "su -" to root, logname won't print
"root" but the normal user.
However, what most people will understand under the "the current user"
would be root, in that case.
Man AND info pages of whoami say:
"print effective userid"
However, it's the user name, that is printed, not the userid (which
most people will understand as the numerical UID).