NAME

MPI_Type_create_struct - Construct a new type using multiple other types

SYNOPSIS

#include <mpi.h> 
int MPI_Type_create_struct(int count , int *b_len , MPI_Aint *disp , MPI_Datatype *oldtype ,
	 MPI_Datatype *newtype ); 
#include <pmpi.h> 
int PMPI_Type_create_struct(int count , int *b_len , MPI_Aint *disp , MPI_Datatype *oldtype ,
	 MPI_Datatype *newtype ); 
#include <mpi.h> 
static MPI::Datatype MPI::Datatype::Create_struct(int count , const int *blen ,
	 const MPI::Aint *disp , const MPI::Datatype *oldtype ); 
INCLUDE 'mpif.h' 
MPI_TYPE_CREATE_STRUCT(count , b_len , disp , oldtype , newtype ,  ierr ) 
INTEGER  count ,  b_len (*),  oldtype (*),  newtype ,  ierr 
INTEGER(KIND=MPI_ADDRESS_KIND)	disp (*) 

INPUT PARAMETERS

count - number of component types (integer)

b_len - block lengths for each component (array of integers)

disp - block displacements in bytes (array of integers)

oldtype - component types (array of handles)

OUTPUT PARAMETER

newtype - newly constructed type (handle)

DESCRIPTION

The MPI_Type_create_struct() function is used to create a new type from a set of count smaller component types. The smaller types oldtype are in block lengths described in the b_len array, and offset from the start of the type by displacements within the disp array.

Note that MPI_Type_struct() is a similar function. However, in FORTRAN, the displacements are only 32-bits. Hence, that function is deprecated, and this function should be used instead.

The type newtype created by this function should be commited with MPI_Type_commit() if it is to be used with message passing functions. The type should be eventually freed with the MPI_Type_free() function.

The C++ version of this function passes the new type via the return value.

PMPI_Type_create_struct() is the profiling version of this function.

ERRORS

All MPI routines except for MPI_Wtime and MPI_Wtick return an error code. The the current MPI error handler is invoked if the return value is not MPI_SUCCESS. The default error handler aborts, but this may be changed with by using the MPI_Errhandler_set() function. The predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned instead. Note that MPI does not guarentee that an MPI program can continue past an error. In this implementation, all errors except MPI_ERR_INTERN or MPI_ERR_OTHER should always be recoverable.

In C, the error code is passed as the return value. In FORTRAN, all functions have an parameter ierr which returns the error code. MPI C++ functions do not directly return an error code. However, C++ users may want to use the MPI::ERRORS_THROW_EXCEPTIONS handler. This will throw an MPI::Exception with the corresponding error code. To prevent exceptions from being raised from within C and Fortran code, they will see all error return values as MPI_ERR_PENDING when this handler is chosen. In this implementation, call MPI::throw_exception() to throw the correct exception if this occurs.

MPI_SUCCESS - No error;

MPI_ERR_PENDING - Pending exception;

MPI_ERR_COUNT - Invalid count;

MPI_ERR_ARG - Invalid pointer;

MPI_ERR_TYPE - Invalid type;

MPI_ERR_INTERN - Out of Memory.

SEE ALSO

MPI_Type_free (3) MPI_Type_struct (3) MPI_Type_contiguous (3) MPI_Type_indexed (3) MPI_Type_hindexed (3) MPI_Type_create_hindexed (3) MPI_Type_vector (3) MPI_Type_hvector (3) MPI_Type_create_hvector (3)

• Lockless
• MPI Documentation
• MPI_Type_create_struct