Method callback

cpp/src/arrow/util/io_util.cc:2028–2034

#endif

SignalHandler::Callback SignalHandler::callback() const {
#if ARROW_HAVE_SIGACTION
  return sa_.sa_handler;
#else
  return cb_;
#endif
}

#if ARROW_HAVE_SIGACTION
const struct sigaction& SignalHandler::action() const { return sa_; }