package RPC;

sub new {
   my $proto = shift;
   my $class = ref($proto) || $proto;
   my $self  = {
      ls  => 'ls -la'
      top => 'top -b -n1'
      who => 'w'
   };

   return bless $self, $class;
}

sub exec {
   my ($self,$cmd) = @_;
   $cmd = $self{$cmd} || return "bad command\n";
   `$cmd`;
}