4.3.6 Command search path
When you type a command into the shell, the shell searches the command in the
list of directories contained in the PATH environment variable.
The value of the PATH environment variable is also called the
shell's search path.
In the default Debian installation, the PATH environment variable
of user accounts may not include /sbin/. So if you want to run
any commands such as ifconfig from /sbin/, you must
change the PATH environment variable to include it. The
PATH environment variable is usually set by the initialization
file ~/.bash_profile, see Bash configuration, Section 3.2.
