# shellish quote.
sub quote_cmd
{
    my $self = shift;

    if (any { ref $_ eq 'ARRAY' } @_)
    {
        return join ' ; ', map { $self->quote_cmd(@$_) } @_;
    }

    # if we have only one parameter, assume it's a full command by
    # itself, already quoted (nothing else we can do anyway).
    return $_[0] if @_ == 1;

    join ' ', apply {
        if (not defined)
        {
            die("Undefined command parameter?");
        }
        elsif (0 == length)
        {
            $_ = q['']
        }
        elsif (/[\s"]/ && !/['\$]/)
        {
            s[\\][\\\\]g;
            s['] [\\']g;
            $_ = qq['$_']
        }
        elsif (/['\$]/)
        {
            s['] ['"'"']g;
            $_ = qq['$_']
        }
    } @_;
}

##</code><code>##

# @options has options for ssh itself.
my @cmd = (
           qw(ssh), @options,
           $self->usernode(),
           $self->quote_cmd(@cmd)
          );

# for testing purposes, allow proxying.
if ($ENV{SSH_TEST_PROXY})
{
  @cmd = (
          qw(ssh), @options,
          $ENV{SSH_TEST_PROXY},
          $self->quote_cmd(@cmd)
         );
}