Who command – This command shows information about all users who are currently logged in to system.
whoami command - This command show the information about current terminal logged user name.
which – This command show the absolute path of any command
Get information about all logged in user
# who
Get informaiton about who logged in and when system last reboot
# who -a
system boot 2020-12-26 17:31
run-level 5 2020-12-26 17:32
devteam ? :0 2020-12-26 17:32 ? 2713 (:0)
shahzad + pts/2 2020-12-26 22:52 00:05 16625 (192.168.0.7)
Check last system reboot time using who command
# who -b
system boot 2020-12-26 17:31
Check system running wih wich runlevel
# who -r
run-level 5 2020-12-26 17:32
check current logged in terminal user
# whoami
Check command executable path
# which who
/usr/bin/who
# which ls
/bin/ls