how to interpret the error codes of boost::mpi?

Question

How to make sense of the boost::mpi error code? For instance, what does error code 834983239 mean?

...
mpi::communicator world;
mpi::request req = world.isend(1, 1, std::string("hello"));
while(!req.test()) {
  boost::this_thread::sleep(boost::posix_time::seconds(1));
}
int errorCode = req.test()->error();
...

Answer 1

The error code is unlikely to be filled in if there was not an error (and the default behavior for Boost.MPI is to throw an exception on error, not return a code). You should not need to check error codes manually unless you have changed Boost.MPI's default error handling settings.