interp.wrongNumArgs(1, args, "?level? command ?arg ...?");
      return interp.ERROR;
    }
  });

  /* ==================== command upvar ===================================== */
  interp.registerCommand("::upvar", function (interp, args) {
//print("UPVAR!"+args+"!");
    args.shift();
    this.requireMinArgc(args, 2, "upvar", "");
    var arg1 = args[0];
    var have_level = 0;
    var have_integer_level = 0;
    var index_ptr = new Array();
    var err_msg_ptr = new Array();

    if (this.isLevel.test((arg1))) {
      have_level = 1;
      args.shift();
      if (this.isInteger.test(arg1)) {
        have_integer_level = 1;
      } else {
	arg1 = arg1.substring(1);
      }
    } else {
      have_level = 1;
      have_integer_level = 1;
      arg1 = "1";
    }
    arg1 = parseInt(arg1);
    interp.upvar_dist = parseInt(arg1);
    interp.in_upvar = 1;
    if (interp.eval_statement.level < arg1) {
        throw "bad level \""+arg1+"\" interp level: "+interp.eval_statement.level;
    }
    var my_flags = 0;
    while (args.length > 0) {
      if (args.length == 1) {
        throw "must be an even number of references"
      }
      var create = 1;

      var to_var = args.shift().toString();
      var my_var = args.shift().toString();
//print("upvar to_var!"+to_var+"!my_var!"+my_var+"!arg1!"+arg1+"!intplv!"+interp.eval_statement.level+"!");
      interp.eval_statement.level -= arg1;
      var var_to_obj = interp.global_ns_ptr.lookupVariableEx(interp, to_var, interp.FUNCTION_FLAGS_LEAVE_ERR_MSG, "access", 0, 0);


      interp.eval_statement.level += arg1;

      if (var_to_obj == null) {
        interp.code = this.ERROR;
	return "";
      }
      var my_var_obj = interp.variable_obj_type.lookupSimpleVar(interp, my_var, my_flags|this.VAR_LOOKUP_AVOID_RESOLVERS, create, err_msg_ptr, index_ptr);
      err_msg_ptr = err_msg_ptr[0];

      if (my_var_obj == null) {
        interp.varErrMsg(my_var, null, "create", err_msg_ptr, -1);
	interp.setErrorCode(["TCL", "LOOKUP", "VARNAME", my_name]);
	interp.code = this.ERROR;
	return "";
      }
      if (var_to_obj == my_var_obj) {
        interp.setResult(interp.string_obj_type.newStringObj("can't upvar from variable to itself", -1));
	interp.setErrorCode(["TCL", "UPVAR", "SELF"]);


	interp.code = this.ERROR;
	return "";
      }
      my_var_obj.linkVar(var_to_obj);
    }
    interp.in_upvar = 0;
    interp.code = this.OK;
    return "";
  });

  /* ==================== command unknown ===================================== */
  interp.registerCommand("::unknown", function (interp, args) {
    interp.setResultString("no such command: \""+args[1]+"\"");
    return interp.ERROR;
  });