32v 1m who
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WHO(1) UNIX Programmer's Manual WHO(1)
Contents
NAME
who - who is on the system
SYNOPSIS
who [ who-file ] [ am I ]
DESCRIPTION
_W_h_o, without an argument, lists the login name, terminal name, and login time for each current UNIX user.
Without an argument, _w_h_o examines the /etc/utmp file to obtain its information. If a file is given, that file is examined. Typically the given file will be /usr/adm/wtmp, which contains a record of all the logins since it was created. Then _w_h_o lists logins, logouts, and crashes since the creation of the wtmp file. Each login is listed with user name, terminal name (with `/dev/' suppressed), and date and time. When an argument is given, logouts produce a similar line without a user name. Reboots produce a line with `x' in the place of the device name, and a fossil time indicative of when the system went down.
With two arguments, as in `who am I' (and also `who are you'), _w_h_o tells who you are logged in as.
FILES
/etc/utmp
SEE ALSO
getuid(2), utmp(5)