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()
- 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.