Managing User Environment Variables
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This assigns the original
PATH
variable plus the
/root/newhackingtool
directory to the new
PATH
variable, so the variable contains everything it did
before, plus the new tool directory.
If you examine the contents of the
PATH
variable again, you should see
that this directory has been appended to the end of
PATH
, as shown here:
kali >
echo $PATH
/usr/local/sbin:usr/local/bin:/usr/sbin:/sbin/bin:/root/newhackingtool
Now you can execute
newhackingtool
applications from anywhere on
your system, rather than having to navigate to its directory. The bash shell
will look in all directories listed for your new tool!
N O T E
Adding to
PATH
can be a useful technique for directories you use often, but be careful
not to add too many directories to your
PATH
variable. Because the system will have to
search through each and every directory in
PATH
to find commands, adding a lot of
directories could slow down your terminal and your hacking.
How Not to Add to the PATH Variable
One mistake commonly made by new Linux users is assigning a new direc-
tory, such as
/root/newhackingtool, directly to the
PATH
variable in this way:
kali >
PATH=/root/newhackingtool
kali >
echo $PATH
/root/newhackingtool
If you use this command, your
PATH
variable will
only contain the
/root/
newhackingtool directory and no longer contain the system binaries direc-
tories such as
/bin,
/sbin, and others that hold critical commands. When
you then go to use any of the system commands, you’ll receive the error
command not found
, as shown next, unless you first navigate to the system
binaries directory when you execute the command:
kali >
ls
bash: ls: command not found
Remember that you want to
append to the
PATH
variable, not replace it.
If you’re in doubt, save the contents of the variable somewhere before you
modify it.
