NAME¶
MPI_Type_get_envelope - Returns information about input arguments
associated with a data type.
SYNTAX¶
C Syntax¶
#include <mpi.h>
int MPI_Type_get_envelope(MPI_Datatype datatype, int *num_integers,
int * num_addresses, int *num_datatypes, int *combiner)
Fortran Syntax¶
INCLUDE 'mpif.h'
MPI_TYPE_GET_ENVELOPE( DATATYPE, NUM_INTEGERS, NUM_ADDRESSES,
NUM_DATATYPES, COMBINER, IERROR)
INTEGER DATATYPE, NUM_INTEGERS, NUM_ADDRESSES
INTEGER NUM_DATATYPES, COMBINER, IERROR
C++ Syntax¶
#include <mpi.h>
void MPI::Datatype::Get_envelope(int& num_integers,
int& num_addresses, int& num_datatypes,
int& combiner) const
- datatype
- Data type to access (handle).
OUTPUT PARAMETERS¶
- num_integers
- Number of input integers used in the call constructing combiner
(nonnegative integer).
- num_addresses
- Number of input addresses used in the call constructing combiner
(nonnegative integer).
- num_datatypes
- Number of input data types used in the call constructing combiner
(nonnegative integer).
- combiner
- Combiner (state).
- IERROR
- Fortran only: Error status (integer).
DESCRIPTION¶
For the given data type, MPI_Type_get_envelope returns information on the number
and type of input arguments used in the call that created the data type. The
number-of-arguments values returned can be used to provide sufficiently large
arrays in the decoding routine MPI_Type_get_contents. This call and the
meaning of the returned values is described below. The combiner reflects the
MPI data type constructor call that was used in creating
datatype.
NOTES¶
These are the values that can be returned in
combiner and their
associated calls:
Values Associated Calls
MPI_COMBINER_NAMED a named predefined data type
MPI_COMBINER_DUP MPI_Type_dup
MPI_COMBINER_CONTIGUOUS MPI_Type_contiguous
MPI_COMBINER_VECTOR MPI_Type_vector
MPI_COMBINER_HVECTOR_INTEGER MPI_Type_hvector from Fortran
MPI_COMBINER_HVECTOR MPI_Type_hvector from C or C++
and MPI_Type_create for
all languages
MPI_COMBINER_INDEXED MPI_Type_indexed
MPI_COMBINER_HINDEXED_INTEGER MPI_Type_hindexed from Fortran
MPI_COMBINER_HINDEXED MPI_Type_hindexed from C or C++
and MPI_Type_create_hindexed
for all languages
MPI_COMBINER_INDEXED_BLOCK MPI_Type_create_indexed_block
MPI_COMBINER_STRUCT_INTEGER MPI_Type_struct from Fortran
MPI_COMBINER_STRUCT MPI_Type_struct from C or C++
and MPI_Type_create_struct
for all languages
MPI_COMBINER_SUBARRAY MPI_Type_create_subarray
MPI_COMBINER_DARRAY MPI_Type_create_darray
MPI_COMBINER_F90_REAL MPI_Type_create_f90_real
MPI_COMBINER_F90_COMPLEX MPI_Type_create_f90_complex
MPI_COMBINER_F90_INTEGER MPI_Type_create_f90_integer
MPI_COMBINER_RESIZED MPI_Type_create_resized
If
combiner is MPI_COMBINER_NAMED, then
datatype is a named
predefined data type.
The actual arguments used in the creation call for a data type can be obtained
from the call MPI_Type_get_contents.
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.
SEE ALSO¶
MPI_Type_get_contents