---
layout: page
category_title: Intermediate commands
category-page: intermediate
author: Marco Farace
title: Who/WhoamI
---

<h2>Use: display a list of all logged in users/display info about current user</h2>

<p>The who utility displays a list of all users currently logged on, showing
   for each user the login name, tty name, the date and time of login, and
   hostname if not local. </p>

<p>

Here are just some of the most useful options for this command:

  <ul>

     <li>-b</li><br>   Display time of last system boot.

    <li> -d</li><br>    Print dead processes.

     <li>-H</li><br>    Write column headings above the regular output.

     <li>-m</li><br>    Only print information about the current terminal.  This is the
           POSIX way of saying who am i.

     <li>-q</li><br>    ``Quick mode'': List only the names and the number of users cur-
           rently logged on.  When this option is used, all other options are
           ignored.

     <li>-s</li><br>    List only the name, line and time fields.  This is the default.

     <li>-T</li><br>   Print a character after the user name indicating the state of the
           terminal line: `+' if the terminal is writable; `-' if it is not;
           and `?' if a bad line is encountered.

     <li>-u</li><br>   Print the idle time for each user, and the associated process ID.

     <li>am I</li><br>  Returns the invoker's real user name.

     <li>file</li><br>  By default, who gathers information from the file /var/run/utmpx.
           An alternative file may be specified.

    <ul>
</p>