NAME

       MPI_Type_create_keyval -  Create a datatype attribute key

SYNOPSIS

       #include <mpi.h>
       int
       MPI_Type_create_keyval(MPI_Type_copy_attr_function *cpyfunc,
                              MPI_Type_delete_attr_function *delfunc, int *key,
                              void *extra)

INPUT PARAMETERS

       copyfunc
              - Copy callback function for type_keyval (function)
       delfunc
              - Delete callback function for type_keyval (function)
       extra  - extra state for callback functions

OUTPUT PARAMETER

       key    - key value for future access (integer)

NOTES FOR FORTRAN

       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.

USAGE WITH IMPI EXTENSIONS

       The IMPI standard only supports MPI-1 functions.  Hence, this function  is  currently  not
       designed to operate within an IMPI job.

ERRORS

       If  an  error occurs in an MPI function, the current MPI error handler is called to handle
       it.  By default, this error handler aborts the MPI job.  The error handler may be  changed
       with  MPI_Errhandler_set  ;  the predefined error handler MPI_ERRORS_RETURN may be used to
       cause error values to be returned (in C and Fortran; this error handler is less useful  in
       with  the  C++  MPI  bindings.   The predefined error handler MPI::ERRORS_THROW_EXCEPTIONS
       should be used in C++ if the error value needs to be recovered).  Note that MPI  does  not
       guarantee that an MPI program can continue past an error.

       All  MPI  routines  (except MPI_Wtime and MPI_Wtick ) return an error value; C routines as
       the value of the function and Fortran routines in the last argument.  The C++ bindings for
       MPI  do  not  return  error  values;  instead,  error  values are communicated by throwing
       exceptions of type MPI::Exception (but not by default).  Exceptions are only thrown if the
       error value is not MPI::SUCCESS .

       Note that if the MPI::ERRORS_RETURN handler is set in C++, while MPI functions will return
       upon an error, there will be no way to recover what the actual error value was.
       MPI_SUCCESS
              - No error; MPI routine completed successfully.
       MPI_ERR_TYPE
              -  Invalid  datatype  argument.   May   be   an   uncommitted   MPI_Datatype   (see
              MPI_Type_commit ).
       MPI_ERR_OTHER
              -  Other  error;  the error code associated with this error indicates an attempt to
              use an invalue keyval.
       MPI_ERR_ARG
              - Invalid argument.  Some argument is invalid and is not identified by  a  specific
              error class.  This is typically a NULL pointer or other such error.

SEE ALSO

       MPI_Type_free_keyval(3),            MPI_Type_get_attr(3),            MPI_Type_set_attr(3),
       MPI_Type_delete_attr(3)

MORE INFORMATION

       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/

LOCATION

       tcreatekey.c