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MPI_Get_address(3)                    MPI                   MPI_Get_address(3)


NAME

       MPI_Get_address -  Get the address of a location in memory


SYNOPSIS

       int MPI_Get_address(MPICH2_CONST void *location, MPI_Aint *address)


INPUT PARAMETER

       location
              - location in caller memory (choice)


OUTPUT PARAMETER

       address
              - address of location (address integer)


NOTES

       This routine is provided for both the Fortran and C programmers.  On
       many systems, the address returned by this routine will be the same as
       produced by the C & operator, but this is not required in C and may not
       be true of systems with word- rather than byte-oriented instructions or
       systems with segmented address spaces.

       This routine should be used instead of MPI_Address .


THREAD AND INTERRUPT SAFETY

       This routine is both thread- and interrupt-safe.  This means that this
       routine may safely be used by multiple threads and from within a signal
       handler.


NOTES FOR FORTRAN

       All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK ) have
       an additional argument ierr at the end of the argument list.  ierr is
       an integer and has the same meaning as the return value of the routine
       in C.  In Fortran, MPI routines are subroutines, and are invoked with
       the call statement.

       All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in
       Fortran.

       In Fortran, the integer type is always signed.  This can cause problems
       on systems where the address fits into a four byte unsigned integer but
       the value is larger than the largest signed integer.  For example, a
       system with more than 2 GBytes of memory may have addresses that do not
       fit within a four byte signed integer.  Unfortunately, there is no easy
       solution to this problem, as there is no Fortran datatype that can be
       used here (using a longer integer type will cause other problems, as
       well as surprising users when the size of the integer type is larger
       that the size of a pointer in C).  In this case, it is recommended that
       you use C to manipulate addresses.


ERRORS

       All MPI routines (except MPI_Wtime and MPI_Wtick ) return an error
       value; C routines as the value of the function and Fortran routines in
       the last argument.  Before the value is returned, the current MPI error
       handler is called.  By default, this error handler aborts the MPI job.
       The error handler may be changed with MPI_Comm_set_errhandler (for
       communicators), MPI_File_set_errhandler (for files), and
       MPI_Win_set_errhandler (for RMA windows).  The MPI-1 routine
       MPI_Errhandler_set may be used but its use is deprecated.  The
       predefined error handler MPI_ERRORS_RETURN may be used to cause error
       values to be returned.  Note that MPI does not guarentee that an MPI
       program can continue past an error; however, MPI implementations will
       attempt to continue whenever possible.

       MPI_SUCCESS
              - No error; MPI routine completed successfully.
       MPI_ERR_OTHER
              - Other error; use MPI_Error_string to get more information
              about this error code.


LOCATION

       src/mpi/datatype/get_address.c

                                   9/20/2012                MPI_Get_address(3)

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