who -- Command

Print who is logged in
who [file] [am i]

The command  who prints  the names of  the users who  are logged in  to the
system.  For each user, who prints her name, terminal name, login date, and
login time.  The form who am i prints this information only about yourself.

If  file  is  specified,  who  uses  it  instead  of  /etc/utmp  to  obtain
information about who is logged in.   This is useful, for example, with the
file /usr/adm/wtmp,  which contains a continuous  record of logins, logouts
and reboots.  When file is specified, who displays logouts; otherwise, they
are suppressed.

Files

/etc/utmp -- To get user information

See Also

ac,
commands,
sa

© 2012 by Stephen A. Ness