MPI_Type_struct(3OpenMPI)												 MPI_Type_struct(3OpenMPI)

NAME

       MPI_Type_struct - Creates a struct data type -- use of this routine is deprecated.

SYNTAX

C Syntax
       #include <mpi.h>
       int MPI_Type_struct(int count, int *array_of_blocklengths,
	    MPI_Aint *array_of_displacements, MPI_Datatype *array_of_types,
	    MPI_Datatype *newtype)

Fortran Syntax
       INCLUDE 'mpif.h'
       MPI_TYPE_STRUCT(COUNT, ARRAY_OF_BLOCKLENGTHS,
		 ARRAY_OF_DISPLACEMENTS, ARRAY_OF_TYPES,
		 NEWTYPE, IERROR)
	    INTEGER   COUNT, ARRAY_OF_BLOCKLENGTHS(*)
	    INTEGER   ARRAY_OF_DISPLACEMENTS(*)
	    INTEGER   ARRAY_OF_TYPES(*), NEWTYPE, IERROR

INPUT PARAMETERS

       count	 Number of blocks (integer)  also number of entries in arrays array_of_types,  array_of_displacements, and array_of_blocklengths.

       array_of_blocklengths
		 Number of elements in each block (array).

       array_of_displacements
		 Byte displacement of each block (array).

       array_of_types
		 Type of elements in each block (array of handles to datatype objects).

OUTPUT PARAMETERS

       newtype	 New datatype (handle).

       IERROR	 Fortran only: Error status (integer).

DESCRIPTION

       Note that use of this routine is deprecated as of MPI-2. Use MPI_Type_create_struct instead.

       This deprecated routine is not available in C++.

       MPI_Type_struct	is  the most general type constructor. It further generalizes MPI_Type_hindexed in that it allows each block to consist of
       replications of different datatypes.

       Example: Let type1 have type map

	   {(double, 0), (char, 8)}

       with extent 16. Let B = (2, 1, 3), D = (0, 16, 26), and T = (MPI_FLOAT, type1, MPI_CHAR). Then a call to MPI_Type_struct(3, B, D,  T,  new-
       type) returns a datatype with type map

	   {(float, 0), (float,4), (double, 16), (char, 24),
	   (char, 26), (char, 27), (char, 28)}

       That  is, two copies of MPI_FLOAT starting at 0, followed by one copy of type1 starting at 16, followed by three copies of MPI_CHAR, start-
       ing at 26. (We assume that a float occupies 4 bytes.)

       For more information, see section 3.12.1 of the MPI-1.1 Standard.

NOTES

       If an upperbound is set explicitly by using the MPI datatype MPI_UB, the corresponding index must be positive.

       The MPI-1 Standard originally made vague statements about padding and alignment; this was intended to allow the simple definition of struc-
       tures that could be sent with a count greater than one. For example,
	   struct {int a; char b;} foo;
       may have
	   sizeof(foo) = sizeof(int) + sizeof(char);
       defining  the  extent  of a datatype as including an epsilon, which would have allowed an implementation to make the extent an MPI datatype
       for this structure equal to 2*sizeof(int). However, since different systems might define different paddings, a clarification to	the  stan-
       dard  made epsilon zero. Thus, if you define a structure datatype and wish to send or receive multiple items, you should explicitly include
       an MPI_UB entry as the last member of the structure.  For example, the following code can be used for the structure foo:

	   blen[0] = 1; indices[0] = 0; oldtypes[0] = MPI_INT;
	   blen[1] = 1; indices[1] = &foo.b - &foo; oldtypes[1] = MPI_CHAR;
	   blen[2] = 1; indices[2] = sizeof(foo); oldtypes[2] = MPI_UB;
	   MPI_Type_struct( 3, blen, indices, oldtypes, &newtype );

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++ func-
       tions  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_create_struct
       MPI_Type_create_hindexed

Open MPI 1.2							  September 2006					 MPI_Type_struct(3OpenMPI)