Format
- who[–AabdHilmprsTtuw]
[file]
- who –q[file]
- who am I|i
Description
who displays
information about users who are logged into the system. By default,
the output contains the user's login name, terminal name, and the
time that the user logged in. Normally, who consults
the file /etc/utmpx for information, but you can use the file argument
to specify another accounting file.
When called as:
who am i
or
who am I
who displays
your login name, terminal, and login time. This command works only
in the POSIX locale.
Options
- –A
- Displays all accounting entries.
- –a
- Displays all types of entries. This is equivalent to specifying –AbdHilprTtuw.
- –b
- Displays all entries written at system boot time.
- –d
- Displays entries produced after the death of a process spawned
from /usr/sbin/init.
- –H
- Displays column headings above the output.
- –i
- Displays idle time for users. The idle time is the hours:minutes since
the last activity; a dot (.) means that the terminal has been used
in the last minute, and the string old means
that the terminal has not been used in more than 24 hours, or hasn't
been used since boot time.
- –l
- Displays logged-out user entries.
- –m
- Displays information about current terminal only.
- –p
- Displays entries for processes spawned from /usr/sbin/init.
- –q
- Displays a quick list with the number of users and their names;
other options are ignored.
- –r
- Displays all run-level change entries.
- –s
- Displays only the three fields user name, terminal,
and time of entry.
- –T
- Displays the state of each terminal as a plus sign (+)
if the terminal allows write access to other users, and a minus sign
(–) if write access is denied. who displays
a question mark (?) if the write access cannot be
determined.
- –t
- Displays all time change entries (both old and new time).
- –u
- Displays only entries associated with logged-in users. who enables
this option when you do not provide any options on the command line.
- –w
- Displays the terminal state; this indicates whether the terminal
can be written to.
Files
who uses
the following files:
- /etc/utmpx
- Displays the current
status file.
Localization
who uses
the following localization environment variables:
- LANG
- LC_ALL
- LC_CTYPE
- LC_MESSAGES
- LC_TIME
- NLSPATH
See Localization for more
information.
Exit values
- 0
- Successful completion
- 2
- Failure because of an incorrect command-line option, or because
of too many command-line arguments.
Portability
POSIX.2 User Portability Extension, X/Open Portability Guide.
The utmpx file
format, the options, and the output of who are
totally compatible with UNIX System V.
The –A, –a, –b, –d –i, –l, –p, –r, –s, –t, –w,
and am I options are extensions to the POSIX
standard.
Related information
See the utmpx file
format description in File formats for more
information.