On Feb 19, 2009, at 10:47 AM, George Bosilca wrote:
I fail to find anything about this on the MPI Standard.
MPI doesn't define any errors, does it? :-) I think it falls into the category of "MPI tells you what to do" and doesn't define what happens if you don't do that. MPI_*_SET_ERRHANDLER says you have to pass an errhandler handle. If you pass an invalid one (to include NULL or MPI_ERRHANDLER_NULL), it's an undefined error.
For me passing the NULL error handle to any kind of set handler function should not be an error. It should means that you prefer to not have any error handler triggered on the object.
You want MPI to have *no* error mechanism defined for a given communicator/file/window? That seems kinda broken. Indeed, what you describe sounds a lot like MPI_ERRORS_RETURN -- meaning that you *do* have to set something specifically to get the error handler to effectively be a no-op (not NULL).
To be clear: MPI_ERRHANDLER_NULL is described as an invalid error handler.
-- Jeff Squyres Cisco Systems
