use Env;
use Env qw(PATH HOME TERM);
Env allows environment variables to be treated as simple variables.
The Env::import() function ties environment variables with suitable names
to global Perl variables with the same names. By default it does so with
all existing environment variables (keys %ENV). If the import function receives arguments, it takes them to be a list of
environment variables to tie; it's okay if they don't yet exist.
After an environment variable is tied, merely use it like a normal variable. You may access its value
@path = split(/:/, $PATH);
or modify it
$PATH .= ":.";
however you'd like. To remove a tied environment variable from the environment, assign it the undefined value
undef $PATH;