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MPI_Type_match_size(3) man page (version 1.3.4)

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NAME

       MPI_Type_match_size - Returns an MPI datatype of a given type and size

SYNTAX


C Syntax

       #include <mpi.h>
       int MPI_Type_match_size(int typeclass, int size,
            MPI_Datatype *type)

Fortran Syntax

       INCLUDE 'mpif.h'
       MPI_TYPE_MATCH_SIZE(TYPECLASS, SIZE, TYPE, IERROR)
            INTEGER   TYPECLASS, SIZE, TYPE, IERROR

C++ Syntax

       #include <mpi.h>
       static MPI::Datatype MPI::Match_size(int typeclass, int size)

INPUT PARAMETERS

       typeclass Generic type specifier (integer).

       size      Size, in bytes, of representation (integer).

OUTPUT PARAMETERS

       type      Datatype with correct type and size (handle).

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       The  function returns an MPI datatype matching a local variable of type
       (typeclass, size). The returned type is a reference (handle) to a  pre-
       defined named datatype, not a duplicate. This type cannot be freed.

       The  value  of  typeclass  may  be  set  to  one of MPI_TYPECLASS_REAL,
       MPI_TYPECLASS_INTEGER, or MPI_TYPECLASS_COMPLEX, corresponding  to  the
       desired datatype.

       MPI_type_match_size  can  be  used  to obtain a size-specific type that
       matches a Fortran numeric intrinsic type: first call MPI_Sizeof to com-
       pute  the  variable size, then call MPI_Type_match_size to find a suit-
       able datatype. In  C  and  C++,  use  the  sizeof  builtin  instead  of
       MPI_Sizeof.

       It is erroneous to specify a size not supported by the compiler.

ERRORS

       Almost  all MPI routines return an error value; C routines as the value
       of the function and Fortran routines in the last  argument.  C++  func-
       tions  do  not  return  errors.  If the default error handler is set to
       MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism
       will be used to throw an MPI:Exception object.
       See the MPI man page for a full list of MPI error codes.

SEE ALSO

       MPI_Sizeof
       MPI_Type_get_extent

1.3.4                            Nov 11, 2009           MPI_Type_match_size(3)

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