who(1) DG/UX 4.30 who(1)
NAME
who - who is on the system
SYNOPSIS
who [-uATHlpdbrtasqh] [ file ]
who am i
who am I
DESCRIPTION
Who can list the user's name, terminal line, login time,
elapsed time since activity occurred on the line, and the
process ID of the shell for each current system user. It
examines the /etc/utmp file to get this information, or it
examines file if it is given. Usually, file will be
/etc/wtmp, which contains a history of all the logins since
the file was last created.
Who with the am i or am I option identifies the invoking
user.
Except for the default -s option, the general format for
output from this command is:
name [state] line time activity pid [comment] [exit]
[hostname]
With options, who can list logins, logoffs, reboots, and
changes to the system clock, as well as other processes
spawned by the init process. These options are:
-u Lists only those users 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
activity is 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 /etc/inittab (see inittab(4)). This
can contain information such as where the terminal is
located, the telephone number of the dataset, and the
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who(1) DG/UX 4.30 who(1)
type of terminal if it is hard-wired.
-A Print entries made by the acct(1M) subsystem.
-T Same as the -u option, except that the state of the
terminal line is printed. The state describes whether
someone else can write to that terminal. A + appears
if the terminal is writable by anyone; a - appears if
it is not. Root can write to all lines having a + or
a - in the state field. If a bad line is encountered,
a ? is printed.
-l Lists only those lines on which the system is waiting
for someone to login. The name field in this case is
LOGIN. Other fields are the same as for user entries,
except that the state field does not exist.
-p Lists any other active process that was also spawned
by init. The name field is the name of the program
executed by init as found in /etc/inittab. The state,
line, and activity fields have no meaning. The
comment field shows the id field of the line from
/etc/inittab that spawned this process. See
inittab(4).
-d Displays all processes that have expired and not been
respawned by init. The exit field appears for a dead
process and contains its termination and exit values,
as returned by wait(2). This can be useful in
determining why a process terminated.
-b Indicates the time and date of the last reboot.
-r Indicates the current run-level of the init process.
-t Indicates the last change to the system clock (via the
date(1) command) by root. See su(1).
-a Processes /etc/utmp or the named file with all options
turned on.
-s The default--lists only the name, line, and time
fields.
-H Prints column headings above the regular output.
-q This is a quick who, displaying only the names and the
number of users currently logged on. When this option
is used, all other options except n are ignored.
-n # This option should be used with -q. It lets you
specify the number of users you want to be displayed
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who(1) DG/UX 4.30 who(1)
per line.
-h This option prints host names for remote users
EXAMPLES
$ who am i
user1 tty21 Nov 19 09:54
The above example displays the user who invoked the who
command.
$ who -u
sys_mgr tty01 Nov 19 09:00 1:53 690
donnelly tty02 Nov 19 08:56 0:20 144
crumley tty20 Nov 19 09:32 . 151
user1 tty21 Nov 19 09:54 . 974
user2 tty12 Nov 19 13:19 0:06 1728
The above example shows all users logged onto the system,
which terminal they have logged onto, the date and time, the
amount of time since last activity ("." indicates less than
one minute), and the user's PID.
$ who -b
. system boot Nov 18 21:34
The above example shows the date and time that the system
was last booted.
FILES
/etc/utmp
/etc/wtmp
/etc/inittab
SEE ALSO
date(1), login(1), mesg(1), su(1).
wait(2), inittab(4), utmp(4) in the Programmer's Reference
for the DG/UX System
init(1m) in the System Manager's Reference for the DG/UX
System
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