The utility who(1) displays information about users
currently logged in to the computer. Without options, who(1)
shows for each user the login name, terminal line, and login time.
Options display additional information.
The last two forms,
who am i
who am I
are equivalent to
who -m
By default, who(1) gathers information from the file
/var/adm/utmpx. You can specify an alternate file
(usually /var/adm/wtmpx) as the source of the
information.
The general format of the output is:
name [state]line time [activity] [pid] [host] [exit]
Where the values are:
name
The user's login name.
state
The state of the terminal; see the description of the -T
option.
line
The number of the terminal line (the file under
/dev).
time
Login time.
activity
The number of hours and minutes since activity last occurred. A
dot (.) indicates activity within the last minute; the string
<old> indicates that no activity has occurred for 24
hours.
pid
The process identifier of the user's login process.
host
The name of the host computer, if -f is specified.
exit
The exit status of dead processes.
Available options:
-a
Display all utmpx record types; this is similar to the union of
options -bdprt. Options that control control how things are
displayed are not affected.
-b
Display time and date of last system reboot.
-d
Display list of dead processes (processes that have expired).
This information is displayed in the exit field of the
output. On traditional systems, this option lists processes that
have not been respawned by init(1); since Interix does not
have a traditional UNIX init(1) process, -d lists
only dead processes.
-f
Display the name of the host as the last field in the
output.
-H
Write column headings above the regular output.
-l
(The letter ell.) Display terminal lines waiting for someone to
login. The name field is displayed as LOGIN. This
information is not currently stored in the Interix subsystem, so
this option is not yet useful.
-m
Return information about the current terminal only.
-p
List any other process that is currently active and that was
spawned by init(1). Because Interix does not have a
traditional init(1) process, this option is not useful.
-q
Quick output: list only the names and number of users currently
logged on. When this option is used, all other options are
ignored.
-r
Display current run-level of the init(1) process.
Because Interix does not have a traditional init(1) process,
this option is not useful.
-s
List only the name, line, and time fields.
This is the default behavior for who(1).
-t
Display the last change to the system clock. This information
is not currently stored in the Interix subsystem, so this option is
not yet useful.
-T
Display the message state of each terminal; a terminal state is
indicated by the characters +, -, and ?,
defined in the following list.
+
Other users can send messages to the terminal.
-
Other users cannot send messages to the terminal.
?
The state cannot be determined.
-u
Displays idle time for each user; idle time is the time that
has elapsed since any activity occurred at the user's
terminal.