typedef int MPI_Comm_copy_attr_function(MPI_Comm oldcomm, intcomm_keyval,
void *extra_state, void *attribute_val_in,
void *attribute_val_out, int *flag);
typedef int MPI_Comm_delete_attr_function(MPI_Comm comm, intcomm_keyval,
void *attribute_val, void *extra_state);
typedef void MPI_Comm_errhandler_fn(MPI_Comm *, int *, ...);
typedef int MPI_Datarep_conversion_function(void *userbuf,
MPI_Datatype datatype, int count, void *filebuf,
MPI_Offset position, void *extra_state);
typedef int MPI_Datarep_extent_function(MPI_Datatype datatype,
MPI_Aint *file_extent, void *extra_state);
typedef void MPI_File_errhandler_fn(MPI_File *, int *, ...);
typedef int MPI_Grequest_cancel_function(void *extra_state, int complete);
typedef int MPI_Grequest_free_function(void *extra_state);
typedef int MPI_Grequest_query_function(void *extra_state,
MPI_Status *status);
typedef int MPI_Type_copy_attr_function(MPI_Datatype oldtype,
int type_keyval, void *extra_state, void *attribute_val_in,
void *attribute_val_out, int *flag);
typedef int MPI_Type_delete_attr_function(MPI_Datatype type, inttype_keyval,
void *attribute_val, void *extra_state);
typedef int MPI_Win_copy_attr_function(MPI_Win oldwin, int win_keyval,
void *extra_state, void *attribute_val_in,
void *attribute_val_out, int *flag);
typedef int MPI_Win_delete_attr_function(MPI_Win win, int win_keyval,
void *attribute_val, void *extra_state);
typedef void MPI_Win_errhandler_fn(MPI_Win *, int *, ...);