osx man page for mpi_type_lb

MPI_Type_lb(3OpenMPI)													     MPI_Type_lb(3OpenMPI)

NAME
       MPI_Type_lb  - Returns the lower bound of a data type. This may differ from zero if the type was constructed using MPI_LB. Use of this rou-
       tine is deprecated.

SYNTAX
C Syntax
       #include <mpi.h>
       int MPI_Type_lb(MPI_Datatype datatype, MPI_Aint *displacement)

Fortran Syntax
       INCLUDE 'mpif.h'
       MPI_TYPE_LB(DATATYPE, DISPLACEMENT, IERROR)
	    INTEGER   DATATYPE, DISPLACEMENT, IERROR

INPUT PARAMETER
       datatype  Datatype (handle).

OUTPUT PARAMETERS
       displacement
		 Displacement of lower bound from origin, in bytes (integer).

       IERROR	 Fortran only: Error status (integer).

DESCRIPTION
       Note that use of this routine is deprecated as of MPI-2. Please use MPI_Type_get_extent instead.

       This deprecated routine is not available in C++.

       MPI_Type_lb returns the lower bound of a data type.

       The "pseudo-datatypes," MPI_LB and MPI_UB, can be used, respectively, to mark the lower bound (or the upper bound)  of  a  datatype.  These
       pseudo-datatypes  occupy  no  space  (extent  (MPI_LB) = extent (MPI_UB) =0. They do not affect the size or count of a datatype, and do not
       affect the context of a message created with this datatype. However, they do affect the definition of the extent of a datatype and,  there-
       fore, affect the outcome of a replication of this datatype by a datatype constructor.

       In general, if

	   Typemap = {(type0, disp0), ..., (type(n-1), disp(n-1)}

       then the lower bound of Typemap is defined to be

			 (min(j) disp(j)			  if no entry has
	   lb(Typemap) = (					  basic type lb
			 (min(j) {disp(j) such that type(j) = lb} otherwise

       Similarly, the upper bound of Typemap is defined to be

			 (max(j) disp(j) + sizeof((type(j)) + e   if no entry has
	   ub(Typemap) = (					  basic type ub
			 (max(j) {disp(j) such that type(j) = ub} otherwise

       Then

	   extent(Typemap) = ub(Typemap) - lb(Typemap)

       If  type(i)  requires  alignment  to  a	byte address that is a multiple of k(i), then e is the least nonnegative increment needed to round
       extent(Typemap) to the next multiple of max(i) k(i).

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_get_extent

Open MPI 1.2							  September 2006					     MPI_Type_lb(3OpenMPI)