WHO(1)                     Commands and Applications                    WHO(1)

NAME

       who - display who is logged in

SYNOPSIS

       who [am I] [file]

DESCRIPTION

       The utility who displays a list of all users currently logged on, show‐
       ing for each user the login name, tty name, the date and time of login,
       and hostname if not local.

       Available options:

              am I   Returns the invoker's real user name.

              file   By   default,  who  gathers  information  from  the  file
                     /var/run/utmp.  An alternate file may be specified  which
                     is  usually /var/run/wtmp (or /var/run/wtmp.[0-6] depend‐
                     ing on site policy as wtmp can grow quite large and daily
                     versions  may or may not be kept around after compression
                     by ac(8)).  The wtmp file contains a record of every  lo‐
                     gin,  logout,  crash, shutdown and date change since wtmp
                     was last truncated or created.

       If /var/log/wtmp is being used as the file, the user name may be  empty
       or  one of the special characters '|', '}' and '~'.  Logouts produce an
       output line without any user name.  For more information on the special
       characters, see utmp(5).

FILES

       /var/run/utmp
       /var/log/wtmp
       /var/log/wtmp.[0-6]

SEE ALSO

       last(1), users(1), getuid(2), utmp(5)

HISTORY

       A who command appeared in Version 6 AT&T UNIX.



GNO                             26 October 1997                         WHO(1)