NAME

       MPI_Win_create_keyval -  Create an attribute keyval for MPI window objects

SYNOPSIS

       int MPI_Win_create_keyval(MPI_Win_copy_attr_function *win_copy_attr_fn,
                               MPI_Win_delete_attr_function *win_delete_attr_fn,
                               int *win_keyval, void *extra_state)

INPUT PARAMETERS

       win_copy_attr_fn
              - copy callback function for win_keyval (function)
       win_delete_attr_fn
              - delete callback function for win_keyval (function)
       extra_state
              - extra state for callback functions

OUTPUT PARAMETERS

       win_keyval
              - key value for future access (integer)

NOTES

       Default copy and delete functions are available.  These are
       MPI_WIN_NULL_COPY_FN
              - empty copy function
       MPI_WIN_NULL_DELETE_FN
              - empty delete function
       MPI_WIN_DUP_FN
              - simple dup function

RETURN VALUE FROM ATTRIBUTE CALLBACKS

       The  MPI-2 versions of the attribute callbacks should return either MPI_SUCCESS on success
       or a valid MPI error code or class on failure.  The MPI  standard  is  ambiguous  on  this
       point,  but as MPI-2 provides the routines MPI_Add_error_class and MPI_Add_error_code that
       allow the user to define and use MPI error codes and classes.

THREAD AND INTERRUPT SAFETY

       This routine is thread-safe.  This means that this routine may be safely used by  multiple
       threads  without the need for any user-provided thread locks.  However, the routine is not
       interrupt safe.  Typically, this is due to the use of memory allocation routines  such  as
       malloc or other non-MPICH runtime routines that are themselves not interrupt-safe.

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.

ERRORS

       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.  Before the value is
       returned, the current MPI error handler is called.  By default, this error handler  aborts
       the  MPI  job.   The  error  handler  may  be  changed  with  MPI_Comm_set_errhandler (for
       communicators), MPI_File_set_errhandler (for files), and MPI_Win_set_errhandler  (for  RMA
       windows).   The  MPI-1  routine  MPI_Errhandler_set may be used but its use is deprecated.
       The predefined error handler MPI_ERRORS_RETURN may be used to cause  error  values  to  be
       returned.   Note  that  MPI  does  not  guarentee that an MPI program can continue past an
       error; however, MPI implementations will attempt to continue whenever possible.

       MPI_SUCCESS
              - No error; MPI routine completed successfully.
       MPI_ERR_ARG
              - Invalid argument.  Some argument is invalid and is not identified by  a  specific
              error class (e.g., MPI_ERR_RANK ).
       MPI_ERR_OTHER
              - Other error; use MPI_Error_string to get more information about this error code.

                                            11/9/2015                    MPI_Win_create_keyval(3)