W(1)                        General Commands Manual                       W(1)

NAME
     w – display who is logged in and what they are doing

SYNOPSIS
     w [--libxo] [-hin] [user ...]

DESCRIPTION
     The w utility prints a summary of the current activity on the system,
     including what each user is doing.  The first line displays the current
     time of day, how long the system has been running, the number of users
     logged into the system, and the load averages.  The load average numbers
     give the number of jobs in the run queue averaged over 1, 5 and 15
     minutes.

     The fields output are the user's login name, the name of the terminal the
     user is on, the host from which the user is logged in, the time the user
     logged on, the time since the user last typed anything, and the name and
     arguments of the current process.

     The options are as follows:

     --libxo
             Generate output via libxo(3) in a selection of different human
             and machine readable formats.  See xo_parse_args(3) for details
             on command line arguments.

     -h      Suppress the heading.

     -i      Output is sorted by idle time.

     -n      Do not attempt to resolve network addresses (normally w
             interprets addresses and attempts to display them as names).
             When -n is specified more than once, hostnames stored in utmp are
             attempted to resolve to display them as network addresses.

     If one or more user names are specified, the output is restricted to
     those users.

COMPATIBILITY
     The -M, -N, -d, -f, -l, -s, and -w flags are no longer supported.

SEE ALSO
     finger(1), ps(1), uptime(1), who(1), libxo(3), xo_parse_args(3)

HISTORY
     The w command appeared in 3.0BSD.

BUGS
     The notion of the “current process” is muddy.  The current algorithm is
     “the highest numbered process on the terminal that is not ignoring
     interrupts, or, if there is none, the highest numbered process on the
     terminal”.  This fails, for example, in critical sections of programs
     like the shell and editor, or when faulty programs running in the
     background fork and fail to ignore interrupts.  (In cases where no
     process can be found, w prints ‘-’.)

     The CPU time is only an estimate, in particular, if someone leaves a
     background process running after logging out, the person currently on
     that terminal is “charged” with the time.

     Background processes are not shown, even though they account for much of
     the load on the system.

     Sometimes processes, typically those in the background, are printed with
     null or garbaged arguments.  In these cases, the name of the command is
     printed in parentheses.

     The w utility does not know about the new conventions for detection of
     background jobs.  It will sometimes find a background job instead of the
     right one.

     Long hostnames and IPv6 addresses may be truncated.

macOS 15.2                      August 24, 2020                     macOS 15.2