Open MPI logo

Open MPI Development Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Development mailing list

Subject: Re: [OMPI devel] possible bugs and unexpected values in returned errors classes
From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2009-02-19 11:43:48


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