who -qn x[file]
who am iwho am I
The who command can list the user's name,terminal line,login time,elapsed time since activity occured on the line and the process-ID of the command interpreter(shell) for each current unix system user. It examines the /var/adm/utmp file to obtain its information.If file is given , that file, is examined.
The am i or am I option identifies the user invoking the who command.
The general format for output is:
name [state] line time [idle] [pid] [comment] [exit]
The name,line and time information is produced by all options except -q. The state information is produced only by -T; only u and -l produce the idle and pid information; and the comment and exit information is produced only by -a. With options who can list logins , logoffs, reboots and changes to the system clock, as well as other processes generated by the init process.
The options will be discussed in the next post.