// Update the actual server config on disk.
	if err = saveServerConfig(ctx, objectAPI, result.Cfg); err != nil {
		return
	}

	// Write the config input KV to history.
	err = saveServerConfigHistory(ctx, objectAPI, kvBytes)
	return
}

// GetConfigKVHandler - GET /minio/admin/v3/get-config-kv?key={key}
//
// `key` can be one of three forms:

				CreateTime: obj.ModTime, // ModTime is createTime for config history entries.
			}
			if withData {
				data, err := readConfig(ctx, objAPI, obj.Name)
				if err != nil {
					// ignore history file if not readable.
					continue
				}

				data, err = decryptData(data, obj.Name)
				if err != nil {
					// ignore history file that cannot be loaded.
					continue
				}

		}
	}
	return -1
}

// invokeMacro pushes onto the input Stack a Slice that holds the macro definition with the actual
// parameters substituted for the formals.
// Invoking a macro does not touch the PC/line history.
func (in *Input) invokeMacro(macro *Macro) {
	// If the macro has no arguments, just substitute the text.
	if macro.args == nil {
		in.Push(NewSlice(in.Base(), in.Line(), macro.tokens))
		return
	}

		// Config KV history operations.
		if enableConfigOps {
			adminRouter.Methods(http.MethodGet).Path(adminVersion+"/list-config-history-kv").HandlerFunc(adminMiddleware(adminAPI.ListConfigHistoryKVHandler, traceAllFlag)).Queries("count", "{count:[0-9]+}")

	if err = saveServerConfig(ctx, objectAPI, cfg); err != nil {
		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, err), r.URL)
		return
	}

	// Write to the config input KV to history.
	if err = saveServerConfigHistory(ctx, objectAPI, []byte(cfgData)); err != nil {
		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, err), r.URL)
		return
	}

	writeSuccessResponseHeadersOnly(w)
}

		}(i)
	}
	wg.Wait()
}

func TestEmptyReaderConcurrent(t *testing.T) {
	// Test for the race detector, to verify a Read that doesn't yield any bytes
	// is okay to use from multiple goroutines. This was our historic behavior.
	// See golang.org/issue/7856
	r := NewReader([]byte{})
	var wg sync.WaitGroup
	for i := 0; i < 5; i++ {
		wg.Add(2)
		go func() {
			defer wg.Done()
			var buf [1]byte
			r.Read(buf[:])