17.2.390. MPI_Type_create_struct

MPI_Type_create_struct - Creates a structured data type.

17.2.390.1. SYNTAX

17.2.390.1.1. C Syntax

#include <mpi.h>

int MPI_Type_create_struct(int count, int array_of_blocklengths[],
     const MPI_Aint array_of_displacements[], const MPI_Datatype array_of_types[],
     MPI_Datatype *newtype)

17.2.390.1.2. Fortran Syntax (see FORTRAN 77 NOTES)

USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_TYPE_CREATE_STRUCT(COUNT, ARRAY_OF_BLOCKLENGTHS,
             ARRAY_OF_DISPLACEMENTS, ARRAY_OF_TYPES, NEWTYPE, IERROR)
     INTEGER COUNT, ARRAY_OF_BLOCKLENGTHS(*), ARRAY_OF_TYPES(*),
     INTEGER NEWTYPE, IERROR
     INTEGER(KIND=MPI_ADDRESS_KIND) ARRAY_OF_DISPLACEMENTS(*)

17.2.390.1.3. Fortran 2008 Syntax

USE mpi_f08
MPI_Type_create_struct(count, array_of_blocklengths,
             array_of_displacements, array_of_types, newtype, ierror)
     INTEGER, INTENT(IN) :: count, array_of_blocklengths(count)
     INTEGER(KIND=MPI_ADDRESS_KIND), INTENT(IN) ::
     array_of_displacements(count)
     TYPE(MPI_Datatype), INTENT(IN) :: array_of_types(count)
     TYPE(MPI_Datatype), INTENT(OUT) :: newtype
     INTEGER, OPTIONAL, INTENT(OUT) :: ierror

17.2.390.2. INPUT PARAMETERS

  • count: Number of blocks (integer) – also number of entries in arrays array_of_types, array_of_displacements, and array_of_blocklengths.

  • array_of_blocklengths: Number of elements in each block (array of integers).

  • array_of_displacements: Byte displacement of each block (array of integers).

  • array_of_types: Type of elements in each block (array of handles to data-type objects).

17.2.390.3. OUTPUT PARAMETERS

  • newtype: New data type (handle).

  • IERROR: Fortran only: Error status (integer).

17.2.390.4. DESCRIPTION

MPI_Type_create_struct creates a structured data type. This routine replaces MPI_Type_struct, which is now deprecated.

NOTE - This routine replaces MPI_Type_struct, which is deprecated. See the man page MPI_Type_struct for information about that routine.

17.2.390.5. FORTRAN 77 NOTES

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

INTEGER*MPI_ADDRESS_KIND ARRAY_OF_DISPLACEMENTS(*)

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

17.2.390.6. ERRORS

Almost all MPI routines return an error value; C routines as the return result of the function and Fortran routines in the last argument.

Before the error value is returned, the current MPI error handler associated with the communication object (e.g., communicator, window, file) is called. If no communication object is associated with the MPI call, then the call is considered attached to MPI_COMM_SELF and will call the associated MPI error handler. When MPI_COMM_SELF is not initialized (i.e., before MPI_INIT / MPI_INIT_THREAD, after MPI_FINALIZE, or when using the Sessions Model exclusively) the error raises the initial error handler. The initial error handler can be changed by calling MPI_COMM_SET_ERRHANDLER on MPI_COMM_SELF when using the World model, or the mpi_initial_errhandler CLI argument to mpiexec or info key to MPI_COMM_SPAWN[_MULTIPLE]. If no other appropriate error handler has been set, then the MPI_ERRORS_RETURN error handler is called for MPI I/O functions and the MPI_ERRORS_ABORT error handler is called for all other MPI functions.

In the sessions model, the error handler can be set during MPI_Session_init.

Open MPI includes three predefined error handlers that can be used:

MPI_ERRORS_ARE_FATAL: Causes the program to abort all connected MPI processes.
MPI_ERRORS_ABORT:     An error handler that can be invoked on a communicator,
                      window, file, or session. When called on a communicator, it
                      acts as if MPI_ABORT was called on that communicator. If
                      called on a window or file, acts as if MPI_ABORT was called
                      on a communicator containing the group of processes in the
                      corresponding window or file. If called on a session,
                      aborts only the local process.
MPI_ERRORS_RETURN:    Returns an error code to the application.

MPI applications can also implement their own error handlers.

Custom MPI error handlers can be created by calling: MPI_Comm_create_errhandler(3) MPI_File_create_errhandler(3) MPI_Session_create_errhandler(3) MPI_Win_create_errhandler(3)

Predefined and custom error handlers can be set by calling: MPI_Comm_set_errhandler(3) MPI_File_set_errhandler(3) MPI_Session_set_errhandler(3) MPI_Win_set_errhandler(3)

Note that MPI does not guarantee that an MPI program can continue past an error.

See the MPI man page for a full list of MPI error codes.

See the Error Handling section of the MPI-3 standard for more information.