L in u X ba sics for h acke rs g e t t I n g s t a r t e d w I t h

Viewing and Modifying Environment Variables
You can view all your default environment variables by entering 
env
into 
your terminal from any directory:
kali >env
XDG_VTNR=7
SSHAGENT_PID=922
XDG_SESSION_ID=2
XDG_GREETER_DATA_DIR=/var/lib/lightdm/data/root
GLADE_PIXMAP_PATH=:echo
TERM=xterm-256color
SHELL=/bin/bash
--snip--
USER=root
--snip--
PATH=/usr/local/sbin :usr/local/bin:/usr/sbin:/sbin/bin
--snip--
HOME=/root
--snip--
Environment variables are always uppercase, as in 
HOME
, 
PATH
, 
SHELL
, and 
so on. These are only the default environment variables that come on your 
system. A user can also create their own variables, and as you will see, we 
need a different command to include those in the output.
Viewing All Environment Variables
To view all environment variables, including shell variables, local vari-
ables, and shell functions such as any user-defined variables and command 
aliases, use the 
set
command. This command will list all environment vari-
ables unique to your system, which in most cases will give you an output so 
long you won’t be able to view it all on a single screen. You can request to 
view each variable, line by line, in a more accessible fashion using 
set
and 
piping it to the 
more
command, as follows:
kali >set | more
BASH=/bin/bash
BASHOPTS=checkwinsize:cmdlist:complete_fullquote:expand_aliases:extglob.....

---

Managing User Environment Variables
73
BASH_ALIASES=()
BASH_ARGC=([0] = "0")
BASH_ARGV=()
--snip--
Now the list of variables will fill up one screen, line by line, and then stop. 
When you press 
enter
, the terminal advances to the next line, taking you 
to the next variable, so you can scroll through by pressing or holding 
enter
. 
As you might recall from Chapter 2, whenever you use the 
more
command 
for output, you can enter 
q
to quit (or exit) and return to the command 
prompt.