whoami-----Finding out who you are.
who---------Listing who is on the system.
W ----------Listing who is on and what they are doing.
Last --------Listing when a user last logged on
the last tools gets its data from the system file "/var/log/wtmp"
some others command
ps ------To list processes on the system.
ps -S -----the process is on hold at the moment.
ps -Z-----To list the zombie process
ps -u------To list all the processes of a specific user.
ps -aux -----To list all processes by all users on the system.
ps -aux | grep root
ps -aux | grep 13
ps -p 344(PID)-----To list the process whose PID is 344.
IF you find that you need more help . other options are available
Apropos -----Finding the right tool to use
Whatis -------Getting a description of a tool
Usage help----Getting usage help for a tool
Man-----------The online manauals
Info-----------The GNU hypertext Info system
HOWTOs------Other documentation on the system
go on !
linux 查看用户的命令