MPI_TYPE_DUP_FN - Built-in MPI function to simple-mindedly copy datatype attributes.

       The  LAM  Team would like the thank the MPICH Team for the handy program to generate man pages ("doctext"
       from ftp://ftp.mcs.anl.gov/pub/sowing/sowing.tar.gz ), the initial formatting, and some initial text  for
       most of the MPI-1 man pages.

dtype  - communicator (handle)
       key    - key value (integer)
       extra  - extra state
       attrin - in value for attribute

       dupfn.c

LAM/MPI 7.1.4                                       6/24/2006                                 MPI_TYPE_DUP_FN(3)

       For more information, please see the official MPI Forum web site, which contains the  text  of  both  the
       MPI-1 and MPI-2 standards.  These documents contain detailed information about each MPI function (most of
       which is not duplicated in these man pages).

       http://www.mpi-forum.org/

       MPI_TYPE_DUP_FN -  Built-in MPI function to simple-mindedly copy datatype attributes.

       This  function blindly byte-copies attributes on datatypes.  It is the default atrribute-copying function
       for datatypes.  This function will always return MPI_SUCCESS , and flag will always be set to 1.

       The actual copy is performed by the code

       *((void **) attrout) = attrin;

       If this simple assignment is not sufficient for your attributes, you will need to reassign the attribute-
       copying function on relevant keyvals on datatypes with the MPI_Type_keyval_create function.

       All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK ) have an additional argument ierr at the
       end of the argument list.  ierr is an integer and has the same meaning as the return value of the routine
       in C.  In Fortran, MPI routines are subroutines, and are invoked with the call statement.

       All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in Fortran.

attrout
              - out value for attribute
       flag   - 1 if attribute copied successfully, 0 otherwise (logical)

       MPI_Type_keyval_create

       #include <mpi.h>
       int MPI_TYPE_DUP_FN(MPI_Datatype dtype, int key,
                          void *extra, void *attrin, void *attrout,
                          int *flag)