code: public static EnvVars getRemote(VirtualChannel channel) throws IOException, InterruptedException {
          if(channel==null)
              return new EnvVars("N/A","N/A");
          return channel.call(new GetEnvVars());
      }
docs: Obtains the environment variables of a remote peer.
  
  @param channel
  Can be null, in which case the map indicating "N/A" will be returned.
  @return
  A fresh copy that can be owned and modified by the caller.