hpux 10.20 - who (1)



 NAME
      who - who is on the system

 SYNOPSIS
      who [-muTlHqpdbrtasAR] [file]

      who am i

      who am I

 DESCRIPTION
      The who command can list the user's name, terminal line, login time,
      elapsed time since input activity occurred on the line, the user's
      host name, and the process-ID of the command interpreter (shell) for
      each current system user.  It examines the /etc/utmp file to obtain
      its information.  If file is given, that file is examined.  Usually,
      file is /var/adm/wtmp, which contains a history of all of the logins
      since the file was last created.

      The who command with the am i or am I option identifies the invoking
      user.

      Except for the default -s option, the general format for output
      entries is:

           name [state] line time activity pid [comment] [exit]

      With options, who can list logins, logoffs, reboots, and changes to
      the system clock, as well as other processes spawned by the init
      process.

    Options
           -m             Output only information about the current
                          terminal.  This option is equivalent to the am i
                          and am I options described above.

           -u             Lists only those users who are currently logged
                          in.  name is the user's login name.  line is the
                          name of the line as found in the directory /dev.
                          The time field indicates when the user logged in.

                          activity is the number of hours and minutes since
                          input activity last occurred on that particular
                          line.  A dot (.) indicates that the terminal has
                          seen activity in the last minute and is therefore
                          ``current''.  If more than twenty-four hours have
                          elapsed or the line has not been used since boot
                          time, the entry is marked old.  This field is
                          useful when trying to determine whether a person
                          is working at the terminal or not.  The pid is the
                          process-ID of the user's login process.  The

                          comment is the comment field associated with this
                          line as found in /etc/inittab (see inittab(4)).
                          This can contain information about where the
                          terminal is located, the telephone number of the
                          dataset, type of terminal if hard-wired, etc.  If
                          no such information is found, then who prints, as
                          the comment, the user's host name as it was stored
                          in the /etc/utmp or named file.  Note that the
                          user's host name is printed instead of comments
                          from the /etc/inittab file if the -u option is
                          used in conjunction with the -R option.

           -T             Same as the -u option, except that the state of
                          the terminal line is printed.  state describes
                          whether someone else can write to that terminal.
                          A + appears if the terminal is writable by anyone;
                          a - appears if it is not.  root can write to all
                          lines having a + or a - in the state field.  If a
                          bad line is encountered, a ?  is printed.

                          (XPG4 only.) Only the following fields are
                          displayed: name state line time

           -l             Lists only those lines on which the system is
                          waiting for someone to login.  The name field is
                          LOGIN in such cases.  Other fields are the same as
                          for user entries except that the state field does
                          not exist.

           -H             Prints column headings above the regular output.

           -q             A quick who, displaying only the names and the
                          number of users currently logged in.  When this
                          option is used, all other options are ignored.

           -p             Lists any other process which is currently active
                          and has been previously spawned by init.  The name
                          field is the name of the program executed by init
                          as found in /etc/inittab.  The state, line, and
                          activity fields have no meaning.  The comment
                          field shows the id field of the line from
                          /etc/inittab that spawned this process.  See
                          inittab(4).

           -d             This option displays all processes that have
                          expired and have not been respawned by init.  The
                          exit field appears for dead processes and contains
                          the termination and exit values of the dead
                          process (as returned by wait() - see wait(2)).
                          This can be useful in determining why a process
                          terminated.

           -b             Indicates the time and date of the last reboot.

           -r             Indicates the current run-level of the init
                          process.  The last three fields contain the
                          current state of init, the number of times that
                          state has been previously entered, and the
                          previous state.  These fields are updated each
                          time init changes to a different run state.

           -t             Indicates the last change to the system clock (via
                          the date command) by root.  See su(1).

           -a             Processes /etc/utmp or the named file with all
                          options turned on.

           -s             Default.  Lists only the name, line, and time
                          fields.

           -A             When the /var/adm/wtmp file is specified, this
                          option indicates when the accounting system was
                          turned on or off using the startup or shutacct
                          commands (see acctsh(1M)).  The name field is ..
                          The line field is acctg on, acctg off, or a reason
                          that was given as an option to the shutacct
                          command.  The time is the time that the on/off
                          activity occurred.

           -R             Displays the user's host name.  If the user is
                          logged in on a tty, who displays the string
                          returned from gethostname() (see gethostname(2)).
                          If the user is not logged in on a tty and the host
                          name stored in the /etc/utmp or named file has not
                          been truncated when stored (meaning that the
                          entire host name was stored with no loss of
                          information), it is displayed as it was stored.
                          Otherwise, the gethostbyaddr() function is called
                          with the internet address of the host (see
                          gethostent(3N)).  The host name returned by
                          gethostbyaddr() is displayed unless it returns an
                          error, in which case the truncated host name is
                          displayed.

      (XPG4 only.  The -s option can not be used with -d, -a or -T options.
      If -u option is used with -T, the idle time is added to the end of the
      -T format.)

 EXTERNAL INFLUENCES
    Environment Variables
      LANG determines the locale to use for the locale categories when both
      LC_ALL and the corresponding environment variable (beginning with LC_)
      do not specify a locale.  If LANG is not set or is set to the empty

      string, a default of "C" (see lang(5)) is used.

      LC_CTYPE determines the locale for interpretation of sequences of
      bytes of text data as characters (e.g., single- verses multibyte
      characters in arguments and input files).

      LC_TIME determines the format and contents of date and time strings.

      LC_MESSAGES determines the language in which messages are displayed.

      If any internationalization variable contains an invalid setting, who
      behaves as if all internationalization variables are set to "C".  See
      environ(5).

    International Code Set Support
      Single- and multi-byte character code sets are supported.

 EXAMPLES
      Check who is logged in on the system:

           who

      Check whether or not you can write to the terminal that another user
      is using:

           who -T

      and look for a plus (+) after the user ID.

 AUTHOR
      who was developed by AT&T and HP.

 FILES
      /etc/inittab
      /etc/utmp
      /var/adm/wtmp

 SEE ALSO
      date(1), login(1), init(1), mesg(1), su(1), gethostname(2), wait(2),
      gethostent(3N), inittab(4), utmp(4).

 STANDARDS CONFORMANCE
      who: SVID2, SVID3, XPG2, XPG3, XPG4, POSIX.2