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WHO(1) General Commands Manual WHO(1) NAME who -- display who is logged in SYNOPSIS who [-abdHlmqrstTuv] [file] who am i DESCRIPTION The who utility displays a list of all users currently logged on, showing for each user the login name, tty name, the date and time of login, and hostname if not local. Available options: -a Same as --bdlprTtuv. -b Time of last system boot. -d Print dead processes. -H Write column headings above the regular output. -l Print system login processes. -m Only print information about the current terminal. This is the POSIX way of saying who am i. -p Print active processes spawned by init(8). -q ``Quick mode'': List only the names and the number of users currently logged on. When this option is used, all other options are ignored. -r Print the current runlevel. Supported runlevels are: d (DEATH) The system has halted. s (SINGLE_USER) The system is running in single user mode. r (RUNCOM) The system is executing /etc/rc. t (READ_TTYS) The system is processing /etc/ttys. m (MULTI_USER) The system is running in multi-user mode. T (CLEAN_TTYS) The system is in the process of stopping processes associated with terminal devices. c (CATATONIA) The system is in the process of shutting down and will not create new processes. -s List only the name, line and time fields. This is the default. -T Print a character after the user name indicating the state of the terminal line: `+' if the terminal is writable; `-' if it is not; and `?' if a bad line is encountered. -t Print last system clock change. -u Print the idle time for each user, and the associated process ID. -v When printing of more information is requested with -u, this switch can be used to also printed process termination signals, process exit status, session id for windowing and the type of the entry, see documentation of ut_type in getutxent(3). am I Returns the invoker's real user name. file By default, who gathers information from the file /var/run/utmpx. An alternative file may be specified which is usually /var/log/wtmpx (or /var/log/wtmp, or /var/log/wtmpx.[0-6] or /var/log/wtmp.[0-6] depending on site policy as wtmpx can grow quite large and daily versions may or may not be kept around after compression by ac(8)). The wtmpx and wtmp file contains a record of every login, logout, crash, shutdown and date change since wtmpx and wtmp were last truncated or created. If /var/log/wtmpx or /var/log/wtmp are being used as the file, the user name may be empty or one of the special characters '|', '}' and '~'. Logouts produce an output line without any user name. For more information on the special characters, see utmp(5). FILES /var/run/utmp /var/run/utmpx /var/log/wtmp /var/log/wtmp.[0-6] /var/log/wtmpx /var/log/wtmpx.[0-6] SEE ALSO last(1), mesg(1), users(1), getuid(2), utmp(5), utmpx(5) STANDARDS The who utility is expected to conform to IEEE Std 1003.2-1992 (``POSIX.2''). HISTORY A who utility appeared in Version 6 AT&T UNIX. NetBSD 7.1.2 January 17, 2007 NetBSD 7.1.2