utilizador

w
w -h
w -u
w -s
who
who | cut -d' ' -f1 | sort | uniq
users
whoami
id -un
who am i
who mom likes
last jason

https://www.thegeekstuff.com/2009/03/4-ways-to-identify-who-is-logged-i…

adduser user_name

https://www.debian-administration.org/article/2/Adding_new_users

newgrp nome_do_grupo

não sei se funciona! vou ter que reiniciar a sessão para confirmar!?

http://arkaitzj.wordpress.com/2010/03/08/linux-add-user-to-a-group-with…

http://www.debianadmin.com/users-and-groups-administration-in-linux.htm…