MPI_Alloc_mem(3)                   Open MPI                   MPI_Alloc_mem(3)



NAME
       MPI_Alloc_mem  - Allocates a specified memory segment.


SYNTAX
C Syntax
       #include <mpi.h>
       int MPI_Alloc_mem(MPI_Aint size, MPI_Info info, void *baseptr)


Fortran Syntax (see FORTRAN NOTES)
       INCLUDE 'mpif.h'
       MPI_ALLOC_MEM(SIZE, INFO, BASEPTR, IERROR)
            INTEGER INFO, IERROR
            INTEGER(KIND=MPI_ADDRESS_KIND) SIZE, BASEPTR


C++ Syntax
       #include <mpi.h>
       void* MPI::Alloc_mem(MPI::Aint size, const MPI::Info& info)


INPUT PARAMETERS
       size      Size of memory segment in bytes (nonnegative integer).

       info      Info argument (handle).


OUTPUT PARAMETERS
       baseptr   Pointer to beginning of memory segment allocated.

       IERROR    Fortran only: Error status (integer).


DESCRIPTION
       MPI_Alloc_mem allocates size bytes of memory. The starting address of
       this memory is returned in the variable base.



FORTRAN NOTES
       There is no portable FORTRAN 77 syntax for using MPI_Alloc_mem.  There
       is no portable Fortran syntax for using pointers returned from
       MPI_Alloc_mem. However, MPI_Alloc_mem can be used with Sun Fortran
       compilers.

       From FORTRAN 77, you can use the following non-standard declarations
       for the SIZE and BASEPTR arguments:
                  INCLUDE "mpif.h"
                  INTEGER*MPI_ADDRESS_KIND SIZE, BASEPTR

       From either FORTRAN 77 or Fortran 90, you can use "Cray pointers" for
       the BASEPTR argument. Cray pointers are described further in the
       Fortran User's Guide and are supported by many Fortran compilers.  For
       example,

                  INCLUDE "mpif.h"
                  REAL*4 A(100,100)
                  POINTER (BASEPTR, A)
                  INTEGER*MPI_ADDRESS_KIND SIZE

                  SIZE = 4 * 100 * 100
                  CALL MPI_ALLOC_MEM(SIZE,MPI_INFO_NULL,BASEPTR,IERR)

                  ! use A

                  CALL MPI_FREE_MEM(A, IERR)


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.

       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_Free_mem



1.4.1                            Jan 14, 2010                 MPI_Alloc_mem(3)
