typedef struct TFE_MonitoringStringGaugeCell TFE_MonitoringStringGaugeCell;
TF_CAPI_EXPORT extern void TFE_MonitoringStringGaugeCellSet(
    TFE_MonitoringStringGaugeCell* cell, const char* value);
// Retrieves the string value and saves it in the buffer.
TF_CAPI_EXPORT extern const void TFE_MonitoringStringGaugeCellValue(
    TFE_MonitoringStringGaugeCell* cell, TF_Buffer* buf);

// APIs for String Gauge without label.

  virtual Status AddRemoveFunctionNotifier(const string& func,
                                           std::function<void()> notifier) = 0;

  // Same as `AddFunctionDef`, but additionally saves the `stack_traces` under
  // the key of the function definition name (to be retrieved during function
  // instantiation).
  virtual Status AddFunctionDefWithStackTraces(