w - Show who is logged on and what they are doing.
w displays information about the users currently on the
machine, and their processes. The header shows, in this order, the current
time, how long the system has been running, how many users are currently
logged on, and the system load averages for the past 1, 5, and 15
minutes.
The following entries are displayed for each user: login name, the
tty name, the remote host, login time, idle time, JCPU, PCPU, and the
command line of their current process.
The JCPU time is the time used by all processes attached to the
tty. It does not include past background jobs, but does include currently
running background jobs.
The PCPU time is the time used by the current process, named in
the "what" field.
- -h,
--no-header
- Don't print the header.
- -u,
--no-current
- Ignores the username while figuring out the current process and cpu times.
To demonstrate this, do a su and do a w and a w
-u.
- -s, --short
- Use the short format. Don't print the login time, JCPU or PCPU times.
- -t,
--terminal
- Usually w will use either the systemd sessions table or the utmp
file to locate users. In terminal mode w will scan the
terminal devices and locate user sessions this way. This is not a true
count of users, for example a user with two xterms will show up twice, so
the user count in the header will be different. Currently terminal devices
scanned are /dev/tty* and /dev/pts/*.
- -f, --from
- Toggle printing the from (remote hostname) field. The default as
released is for the from field to not be printed, although your
system administrator or distribution maintainer may have compiled a
version in which the from field is shown by default.
- --help
- Display help text and exit.
- -i, --ip-addr
- Display IP address instead of hostname for from field.
- -p, --pids
- Display pid of the login process/the "what" process in the
"what" field. The login process is also called the session
leader.
- -V, --version
- Display version information.
- -o,
--old-style
- Old style output. Prints blank space for idle times less than one
minute.
- user
- Show information about the specified user only.
- PROCPS_USERLEN
- Override the default width of the username column. Defaults to 8.
- PROCPS_FROMLEN
- Override the default width of the from column. Defaults to 16.
- /var/run/utmp
- information about who is currently logged on, only for non-systemd
hosts.
- /proc
- process information
- /dev/tty* , /dev/pts/*
- Terminal device files scanned with --terminal mode.
When using --terminal option, w assumes processes
with a parent PID of 0 or 1 are agetty(8) processes and will not
display them. This is prone to both false postive and negative errors.