def assert_open
    @mutex.synchronize do
      raise Exceptions::NotConnected if !@czk or @czk.closed?
      if forked?
        raise InheritedConnectionError, <<-EOS.gsub(/(?:^|\n)\s*/, ' ').strip
          You tried to use a connection inherited from another process 
          (original pid: #{original_pid}, your pid: #{Process.pid})
          You need to call reopen() after forking
        EOS
      end
    end
  end
def assert_open
    @mutex.synchronize do
      raise Exceptions::NotConnected if !@czk or @czk.closed?
      if forked?
        raise InheritedConnectionError, <<-EOS.gsub(/(?:^|\n)\s*/, ' ').strip
          You tried to use a connection inherited from another process 
          (original pid: #{original_pid}, your pid: #{Process.pid})
          You need to call reopen() after forking
        EOS
      end
    end
  end
if either of these happen, the user will need to renegotiate a connection via reopen