MPI_TYPE_FREE, MPI_Type_free

Purpose

Marks a datatype for deallocation.

C synopsis

#include <mpi.h>
int MPI_Type_free(MPI_Datatype *datatype);

C++ synopsis

#include mpi.h
void MPI::Datatype::Free();

FORTRAN synopsis

include 'mpif.h' or use mpi
MPI_TYPE_FREE(INTEGER DATATYPE,INTEGER IERROR)

Parameters

datatype
     is the datatype to be freed (handle) (INOUT)

IERROR
     is the FORTRAN return code. It is always the last argument.

Description

This subroutine marks the datatype object associated with datatype for
deallocation. It sets datatype to MPI_DATATYPE_NULL. All communication
currently using this datatype completes normally. Derived datatypes defined
from the freed datatype are not affected.

Notes

MPI_FILE_GET_VIEW and MPI_TYPE_GET_CONTENTS both return new references or
handles for existing MPI_Datatypes. Each new reference to a derived type
should be freed after the reference is no longer needed. New references to
named types must not be freed. You can identify a derived datatype by
calling MPI_TYPE_GET_ENVELOPE and checking that the combiner is not
MPI_COMBINER_NAMED. MPI cannot discard a derived MPI_Datatype if there are
any references to it that have not been freed by MPI_TYPE_FREE.

Errors

Invalid datatype

Predefined datatype

Type is already free

MPI not initialized

MPI already finalized

Related information

     MPI_FILE_GET_VIEW
     MPI_TYPE_COMMIT
     MPI_TYPE_GET_CONTENTS