# 18.2.391. MPI_Type_create_resized

MPI_Type_create_resized — Returns a new data type with new extent and upper and lower bounds.

## 18.2.391.1. SYNTAX

### 18.2.391.1.1. C Syntax

    #include <mpi.h>

    int MPI_Type_create_resized(MPI_Datatype oldtype, MPI_Aint lb,
         MPI_Aint extent, MPI_Datatype *newtype)

### 18.2.391.1.2. Fortran Syntax

    USE MPI
    ! or the older form: INCLUDE 'mpif.h'
    MPI_TYPE_CREATE_RESIZED(OLDTYPE, LB, EXTENT, NEWTYPE, IERROR)
         INTEGER OLDTYPE, NEWTYPE, IERROR
         INTEGER(KIND=MPI_ADDRESS_KIND)  LB, EXTENT

### 18.2.391.1.3. Fortran 2008 Syntax

    USE mpi_f08
    MPI_Type_create_resized(oldtype, lb, extent, newtype, ierror)
         INTEGER(KIND=MPI_ADDRESS_KIND), INTENT(IN) :: lb, extent
         TYPE(MPI_Datatype), INTENT(IN) :: oldtype
         TYPE(MPI_Datatype), INTENT(OUT) :: newtype
         INTEGER, OPTIONAL, INTENT(OUT) :: ierror

## 18.2.391.2. INPUT PARAMETERS

- `oldtype`: Input data type (handle).

- `lb`: New lower bound of data type (integer).

- `extent`: New extent of data type (integer).

## 18.2.391.3. OUTPUT PARAMETERS

- `newtype`: Output data type (handle).

- `ierror`: Fortran only: Error status (integer).

## 18.2.391.4. DESCRIPTION

MPI_Type_create_resized returns in newtype a handle to a new data type that is identical to oldtype, except that the lower bound of this new data type is set to be lb, and its upper bound is set to be lb + extent. Any previous lb and ub markers are erased, and a new pair of lower bound and upper bound markers are put in the positions indicated by the lb and extent arguments. This affects the behavior of the data type when used in communication operations, with count > 1, and when used in the construction of new derived data types.

## 18.2.391.5. NOTE

Use of MPI_Type_create_resized is strongly recommended over the legacy MPI-1 functions MPI_Type_extent and MPI_Type_lb.

## 18.2.391.6. 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/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.

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 by calling:

- MPI_Comm_create_errhandler then MPI_Comm_set_errhandler

- MPI_File_create_errhandler then MPI_File_set_errhandler

- MPI_Session_create_errhandler then MPI_Session_set_errhandler or at MPI_Session_init

- MPI_Win_create_errhandler then MPI_Win_set_errhandler

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-3.1 standard for more information.

See also

- MPI_Type_get_extent