Unlike the system log files and the authentication log files, all of these files are binary files. So, we can't use our normal text tools, such as less or grep, to read them or extract information from them. Instead, we'll use some special tools that can read these binary files.
The w and who commands pull information about who's logged in and what they're doing from the /var/run/utmp file. Both commands have their own option switches, but you likely won't ever need them. If you just want to see the list of users who are currently logged in, use who like so:
donnie@orangepione:/var/log$ whodonnie tty7 2019-08-02 18:18 (:0)donnie pts/1 2019-11-21 16:21 (192.168.0.251)donnie pts/2 2019-11-21 17:01 (192.168.0.251) ...
