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MPI_File_get_type_extent(3) man page (version 1.2.9)

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NAME

       MPI_File_get_type_extent  -  Returns  the  extent of the data type in a
       file.

SYNTAX

       C Syntax
           #include <mpi.h>
           int MPI_File_get_type_extent(MPI_File fh, MPI_Datatype
                  datatype, MPI_Aint *extent)

       Fortran Syntax (see FORTRAN 77 NOTES)
           INCLUDE 'mpif.h'
           MPI_FILE_GET_TYPE_EXTENT(FH, DATATYPE, EXTENT,  IERROR)
                 INTEGER   FH, DATATYPE, IERROR
                 INTEGER(KIND=MPI_ADDRESS_KIND) EXTENT

C++ Syntax

       #include <mpi.h>
       MPI::Aint MPI::File::Get_type_extent(const MPI::Datatype&
            datatype) const

INPUT PARAMETERS

       fh        File handle (handle).

       datatype  Data type (handle).

OUTPUT PARAMETERS

       extent    Data type extent (integer).

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       MPI_File_get_type_extent can be used to calculate extent  for  datatype
       in  the  file.  The  extent is the same for all processes accessing the
       file associated with fh. If the current view uses a  user-defined  data
       representation,  MPI_File_get_type_extent uses the dtype_file_extent_fn
       callback to calculate the extent.

FORTRAN 77 NOTES

       The MPI standard prescribes portable  Fortran  syntax  for  the  EXTENT
       argument only for Fortran 90. FORTRAN 77 users may use the non-portable
       syntax

            INTEGER*MPI_ADDRESS_KIND EXTENT

       where MPI_ADDRESS_KIND is a constant defined in mpif.h  and  gives  the
       length of the declared integer in bytes.

NOTES

       If  the  file  data representation is other than "native," care must be
       the data types to match the file data representation. Data types passed
       as  arguments to read/write routines specify the data layout in memory;
       therefore, they must always be constructed using  displacements  corre-
       sponding to displacements in memory.

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.

       Before  the  error  value is returned, the current MPI error handler is
       called. For MPI I/O function errors, the default error handler  is  set
       to   MPI_ERRORS_RETURN.   The   error   handler  may  be  changed  with
       MPI_File_set_errhandler;     the     predefined      error      handler
       MPI_ERRORS_ARE_FATAL  may  be  used to make I/O errors fatal. Note that
       MPI does not guarantee that an MPI program can continue past an  error.

Open MPI 1.2 September 20MPI_File_get_type_extent(3OpenMPI)



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