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who(1) [osx man page]

WHO(1)							    BSD General Commands Manual 						    WHO(1)

who -- display who is logged in SYNOPSIS
who [-abdHlmpqrsTtu] [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 -bdlprTtu. -b Time of last system boot. -d Print dead processes. -H Write column headings above the regular output. -l Print system login processes (unsupported). -m Only print information about the current terminal. This is the POSIX way of saying who am i. -p Print active processes spawned by launchd(8) (unsupported). -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. This is meaningless on Mac OS X. -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 (unsupported). -u Print the idle time for each user, and the associated process ID. 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. FILES
/var/run/utmpx SEE ALSO
last(1), mesg(1), users(1), getuid(2), utmpx(5) STANDARDS
The who utility conforms to IEEE Std 1003.1-2001 (``POSIX.1''). HISTORY
A who utility appeared in Version 6 AT&T UNIX. BSD
January 17, 2007 BSD

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who(1)								   User Commands							    who(1)

who - who is on the system SYNOPSIS
/usr/bin/who [-abdHlmpqrstTu] [file] /usr/bin/who -q [-n x] [file] /usr/bin/who am i /usr/bin/who am I /usr/xpg4/bin/who [-abdHlmpqrtTu] [file] /usr/xpg4/bin/who -q [-n x] [file] /usr/xpg4/bin/who -s [-bdHlmpqrtu] [file] /usr/xpg4/bin/who am i /usr/xpg4/bin/who am I DESCRIPTION
The who utility can list the user's name, terminal line, login time, elapsed time since activity occurred on the line, and the process-ID of the command interpreter (shell) for each current UNIX system user. It examines the /var/adm/utmpx file to obtain its information. If file is given, that file (which must be in utmpx(4) format) is examined. Usually, file will be /var/adm/wtmpx, which contains a history of all the logins since the file was last created. The general format for output is: name [state] line time [idle] [pid] [comment] [exit] where: name User's login name state Capability of writing to the terminal line Name of the line found in /dev time Time since user's login idle Time elapsed since the user's last activity pid User's process id comment Comment line in inittab(4) exit Exit status for dead processes OPTIONS
The following options are supported: -a Processes /var/adm/utmpx or the named file with -b, -d, -l, -p, -r, -t, -T, and -u options turned on. -b Indicates the time and date of the last reboot. -d Displays all processes that have expired and not been respawned by init. The exit field appears for dead processes and contains the termination and exit values (as returned by wait(3UCB)), of the dead process. This can be useful in determining why a process terminated. -H Outputs column headings above the regular output. -l Lists only those lines on which the system is waiting for someone to login. The name field is LOGIN in such cases. Other fields are the same as for user entries except that the state field does not exist. -m Outputs only information about the current terminal. -n x Takes a numeric argument, x, which specifies the number of users to display per line. x must be at least 1. The -n option can only be used with -q. -p Lists any other process that is currently active and has been previously spawned by init. The name field is the name of the pro- gram executed by init as found in /sbin/inittab. The state, line, and idle fields have no meaning. The comment field shows the id field of the line from /sbin/inittab that spawned this process. See inittab(4). -q (Quick who) Displays only the names and the number of users currently logged on. When this option is used, all other options are ignored. -r Indicates the current run-level of the init process. -s (Default) Lists only the name, line, and time fields. /usr/bin/who -T Same as the -s option, except that the state idle, pid, and comment, fields are also written. state is one of the following char- acters: + The terminal allows write access to other users. - The terminal denies write access to other users. ? The terminal write-access state cannot be determined. /usr/xpg4/bin/who -T Same as the -s option, except that the state field is also written. state is one of the characters listed under the /usr/bin/who version of this option. If the -u option is used with -T, the idle time is added to the end of the previous format. -t Indicates the last change to the system clock (using the date utility) by root. See su(1M) and date(1). -u Lists only those users who are currently logged in. The name is the user's login name. The line is the name of the line as found in the directory /dev. The time is the time that the user logged in. The idle column contains the number of hours and minutes since activity last occurred on that particular line. A dot (.) indicates that the terminal has seen activity in the last minute and is therefore ``current.'' If more than twenty-four hours have elapsed or the line has not been used since boot time, the entry is marked old. This field is useful when trying to determine whether a person is working at the terminal or not. The pid is the process-ID of the user's shell. The comment is the comment field associated with this line as found in /sbin/inittab (see init- tab(4)). This can contain information about where the terminal is located, the telephone number of the dataset, type of terminal if hard-wired, and so forth. OPERANDS
The following operands are supported: am i In the "C" locale, limits the output to describing the invoking user, equivalent to the -m option. The am and i or I must be sepa- am I rate arguments. file Specifies a path name of a file to substitute for the database of logged-on users that who uses by default. ENVIRONMENT VARIABLES
See environ(5) for descriptions of the following environment variables that affect the execution of who: LANG, LC_ALL, LC_CTYPE, LC_MES- SAGES, LC_TIME, and NLSPATH. EXIT STATUS
The following exit values are returned: 0 Successful completion. >0 An error occurred. FILES
/sbin/inittab Script for init /var/adm/utmpx Current user and accounting information /var/adm/wtmpx Historic user and accounting information ATTRIBUTES
See attributes(5) for descriptions of the following attributes: /usr/bin/who +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ /usr/xpg4/bin/who +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWxcu4 | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ SEE ALSO
date(1), login(1), mesg(1), init(1M), su(1M), wait(3UCB), inittab(4), utmpx(4), attributes(5), environ(5), standards(5) NOTES
Superuser: After a shutdown to the single-user state, who returns a prompt. Since /var/adm/utmpx is updated at login time and there is no login in single-user state, who cannot report accurately on this state. The command, who am i, however, returns the correct information. SunOS 5.10 3 Nov 2000 who(1)

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