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[netCDF #QOI-309912]: netcdf4 MPI_Comm Problem with Open MPI

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  • Subject: [netCDF #QOI-309912]: netcdf4 MPI_Comm Problem with Open MPI
  • Date: Thu, 14 Jan 2010 14:49:36 -0700
> Hi,
> 
> I started using NetCDF4 for parallel I/O. As I'm using Open MPI, I
> soon ran into the problem discussed on the mailing list:
> 
> http://www.unidata.ucar.edu/mailing_lists/archives/netcdfgroup/2009/msg00026.html
> 
> The appended patch implements an additional wrapper around nc_open_par and
> nc_create_par when calling these C functions from Fortran. These
> wrappers do the necessary conversion of the MPI communicator and the
> MPI info object.
> In my opinion something like this should soon go into a release, because
> this problem annoys all Open MPI users.
> 
> matthias
> 
> 
> 

Howdy Matthias!

Sorry it has taken so long to get back to you on this. Things have been a 
little busy here.

My question is this: what happens to the MPI_Comm_f2c function in an MPICH2 
based parallel I/O program.

That is, are these functions only defined for Open MPI? If so, I need some 
macro that openMPI sets so that my C code can know when to use these functions.

Thanks,

Ed

Ticket Details
===================
Ticket ID: QOI-309912
Department: Support netCDF
Priority: Critical
Status: Open