#!D:\perl\bin\perl
use strict;

my ($Reg, $Host, $Key, $Value);
use Win32::TieRegistry ( 
    TiedRef => \$Reg, 
    ArrayValues => 1, 
    Delimiter => '/', 
    ':REG_' 
);

# Asking for machine name and info to be added to the sys env var
print "What host would you like to connect to? ";
chomp($Host = <STDIN>);
print "What name would you like for the Sys Environment Variable? ";
chomp($Key = <STDIN>);
print "What value would you like to assign to this variable? ";
chomp($Value = <STDIN>);

# this is the system environment variable area done on the registry
my $SysEnv= $Reg->Connect("$Host", "LMachine/System/CurrentControlSet/Control/Session Manager/Environment/") 
    or  die "Can't connect to $Host 's registry or can't open Registry key, Session Manager/Environment: $^E
+\n";

# create a new value and set it's data
$SysEnv->{"/$Key"} = "$Value";