NAME

       MPI_Get, MPI_Rget - Copies data from the target memory to the origin.

SYNTAX

C Syntax

       #include <mpi.h>
       MPI_Get(void *origin_addr, int origin_count, MPI_Datatype
            origin_datatype, int target_rank, MPI_Aint target_disp,
            int target_count, MPI_Datatype target_datatype, MPI_Win win)

       MPI_Rget(void *origin_addr, int origin_count, MPI_Datatype
             origin_datatype, int target_rank, MPI_Aint target_disp,
             int target_count, MPI_Datatype target_datatype, MPI_Win win,
                MPI_Request *request)

Fortran Syntax (see FORTRAN 77 NOTES)

       USE MPI
       ! or the older form: INCLUDE 'mpif.h'
       MPI_GET(ORIGIN_ADDR, ORIGIN_COUNT, ORIGIN_DATATYPE, TARGET_RANK,
            TARGET_DISP, TARGET_COUNT, TARGET_DATATYPE, WIN, IERROR)
            <type> ORIGIN_ADDR(*)
            INTEGER(KIND=MPI_ADDRESS_KIND) TARGET_DISP
            INTEGER ORIGIN_COUNT, ORIGIN_DATATYPE, TARGET_RANK,
            TARGET_COUNT, TARGET_DATATYPE, WIN, IERROR

       MPI_RGET(ORIGIN_ADDR, ORIGIN_COUNT, ORIGIN_DATATYPE, TARGET_RANK,
             TARGET_DISP, TARGET_COUNT, TARGET_DATATYPE, WIN, REQUEST, IERROR)
             <type> ORIGIN_ADDR(*)
             INTEGER(KIND=MPI_ADDRESS_KIND) TARGET_DISP
             INTEGER ORIGIN_COUNT, ORIGIN_DATATYPE, TARGET_RANK,
             TARGET_COUNT, TARGET_DATATYPE, WIN, REQUEST, IERROR

Fortran 2008 Syntax

       USE mpi_f08
       MPI_Get(origin_addr, origin_count, origin_datatype, target_rank,
                 target_disp, target_count, target_datatype, win, ierror)
            TYPE(*), DIMENSION(..), ASYNCHRONOUS :: origin_addr
            INTEGER, INTENT(IN) :: origin_count, target_rank, target_count
            TYPE(MPI_Datatype), INTENT(IN) :: origin_datatype, target_datatype
            INTEGER(KIND=MPI_ADDRESS_KIND), INTENT(IN) :: target_disp
            TYPE(MPI_Win), INTENT(IN) :: win
            INTEGER, OPTIONAL, INTENT(OUT) :: ierror

       MPI_Rget(origin_addr, origin_count, origin_datatype, target_rank,
            target_disp, target_count, target_datatype, win, request,
                 ierror)
            TYPE(*), DIMENSION(..), ASYNCHRONOUS :: origin_addr
            INTEGER, INTENT(IN) :: origin_count, target_rank, target_count
            TYPE(MPI_Datatype), INTENT(IN) :: origin_datatype, target_datatype
            INTEGER(KIND=MPI_ADDRESS_KIND), INTENT(IN) :: target_disp
            TYPE(MPI_Win), INTENT(IN) :: win
            TYPE(MPI_Request), INTENT(OUT) :: request
            INTEGER, OPTIONAL, INTENT(OUT) :: ierror

C++ Syntax

       #include <mpi.h>
       void MPI::Win::Get(const void *origin_addr, int origin_count,
            const MPI::Datatype& origin_datatype, int target_rank,
            MPI::Aint target_disp, int target_count,
            const MPI::Datatype& target_datatype) const

INPUT PARAMETERS

       origin_addr
                 Initial address of origin buffer (choice).

       origin_count
                 Number of entries in origin buffer (nonnegative integer).

       origin_datatype
                 Data type of each entry in origin buffer (handle).

       target_rank
                 Rank of target (nonnegative integer).

       target_disp
                 Displacement   from   window  start  to  the  beginning  of  the  target  buffer
                 (nonnegative integer).

       target_count
                 Number of entries in target buffer (nonnegative integer).

       target datatype
                 datatype of each entry in target buffer (handle)

       win       window object used for communication (handle)

OUTPUT PARAMETER

       request   MPI_Rget: RMA request

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       MPI_Get copies data from the target memory to the origin, similar to MPI_Put, except  that
       the  direction  of  data  transfer  is  reversed.  The  origin_datatype  may  not  specify
       overlapping entries in the origin buffer. The target buffer must be contained  within  the
       target  window,  and  the  copied data must fit, without truncation, in the origin buffer.
       Only processes within the same node can access the target window.

       MPI_Rget is similar to MPI_Get, except that it allocates a  communication  request  object
       and  associates it with the request handle (the argument request) that can be used to wait
       or test for completion. The completion of an MPI_Rget operation indicates that the data is
       available in the origin buffer. If origin_addr points to memory attached to a window, then
       the data becomes available in the private copy of this window.

FORTRAN 77 NOTES

       The MPI standard prescribes portable Fortran syntax for the TARGET_DISP argument only  for
       Fortran 90. FORTRAN 77 users may use the non-portable syntax

            INTEGER*MPI_ADDRESS_KIND TARGET_DISP

       where  MPI_ADDRESS_KIND  is  a  constant  defined  in  mpif.h  and gives the length of the
       declared integer in bytes.

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_Put