.\"Copyright 2006-2008 Sun Microsystems, Inc.
.\" Copyright (c) 1996 Thinking Machines Corporation
.TH MPI_Type_get_extent 3 "Dec 08, 2009" "1.4" "Open MPI"
.SH NAME
\fBMPI_Type_get_extent\fP \- Returns the lower bound and extent of a data type. 

.SH SYNTAX
.ft R
.SH C Syntax
.nf
#include <mpi.h>
int MPI_Type_get_extent(MPI_Datatype \fIdatatype\fP, MPI_Aint\fI *lb\fP, 
	MPI_Aint *\fIextent\fP)

.SH Fortran Syntax (see FORTRAN 77 NOTES)
.nf
INCLUDE 'mpif.h'
MPI_TYPE_GET_EXTENT(\fIDATATYPE, LB, EXTENT, IERROR\fP)
	INTEGER	\fIDATATYPE, IERROR\fP 
	INTEGER(KIND=MPI_ADDRESS_KIND) \fILB, EXTENT\fP

.SH C++ Syntax
.nf
#include <mpi.h>
void MPI::Datatype::Get_extent(MPI::Aint& \fIlb\fP, MPI::Aint& \fIextent\fP) 
	const

.SH INPUT PARAMETER
.ft R
.TP 1i
datatype      
Data type (handle).
.sp
.SH OUTPUT PARAMETERS
.ft R
.TP 1i
lb
Lower bound of data type (integer).
.TP 1i
extent      
Data type extent (integer).
.ft R
.TP 1i
IERROR
Fortran only: Error status (integer). 

.SH DESCRIPTION
.ft R
MPI_Type_get_extent returns the lower bound and the extent of \fIdatatype\fP.

.SH NOTE
.ft R
Use of MPI_Type_get_extent is strongly recommended over the old MPI-1 functions MPI_Type_extent and MPI_Type_lb. 

.SH FORTRAN 77 NOTES
.ft R
The MPI standard prescribes portable Fortran syntax for
the \fILB\fP and \fIEXTENT\fP arguments only for Fortran 90. FORTRAN 77
users may use the non-portable syntax
.sp
.nf
     INTEGER*MPI_ADDRESS_KIND \fILB\fP
or
     INTEGER*MPI_ADDRESS_KIND \fIEXTENT\fP
.fi
.sp
where MPI_ADDRESS_KIND is a constant defined in mpif.h
and gives the length of the declared integer in bytes.

.SH 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.
.sp
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.