NAME

       MPI_Type_commit - Commits a data type.

SYNTAX

C Syntax

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

Fortran Syntax

       INCLUDE 'mpif.h'
       MPI_TYPE_COMMIT(DATATYPE, IERROR)
            INTEGER   DATATYPE, IERROR

C++ Syntax

       #include <mpi.h>
       void Datatype::Commit()

INPUT PARAMETER

       datatype  Data type (handle).

OUTPUT PARAMETER

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       The  commit  operation  commits  the data type. A data type is the formal description of a
       communication buffer, not the  content  of  that  buffer.  After  a  data  type  has  been
       committed, it can be repeatedly reused to communicate the changing content of a buffer or,
       indeed, the content of different buffers, with different starting addresses.

       Example: The following Fortran code fragment gives examples of using MPI_Type_commit.

           INTEGER type1, type2
           CALL MPI_TYPE_CONTIGUOUS(5, MPI_REAL, type1, ierr)
                         ! new type object created
           CALL MPI_TYPE_COMMIT(type1, ierr)
                         ! now type1 can be used for communication

       If the data type specified in datatype is already committed, it is equivalent to a no-op.

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++ functions 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. By default,
       this error handler aborts the MPI job, except for I/O function errors. The  error  handler
       may    be   changed   with   MPI_Comm_set_errhandler;   the   predefined   error   handler
       MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not
       guarantee that an MPI program can continue past an error.