NAME

       MPI_Rget_accumulate -  Perform an atomic, one-sided read-and-accumulate

SYNOPSIS

       int MPI_Rget_accumulate(const void *origin_addr, int origin_count,
       MPI_Datatype origin_datatype, void *result_addr,
       int result_count, MPI_Datatype result_datatype,
       int target_rank, MPI_Aint target_disp, int target_count,
       MPI_Datatype target_datatype, MPI_Op op, MPI_Win win,
       MPI_Request *request)

       int MPI_Rget_accumulate_c(const void *origin_addr, MPI_Count origin_count,
       MPI_Datatype origin_datatype, void *result_addr,
       MPI_Count result_count, MPI_Datatype result_datatype,
       int target_rank, MPI_Aint target_disp,
       MPI_Count target_count, MPI_Datatype target_datatype,
       MPI_Op op, MPI_Win win, MPI_Request *request)

INPUT PARAMETERS

       origin_addr
              - initial address of buffer (choice)
       origin_count
              - number of entries in origin buffer (non-negative integer)
       origin_datatype
              - datatype of each entry in origin buffer (handle)
       result_count
              - number of entries in result buffer (non-negative integer)
       result_datatype
              - datatype of entries in result buffer (handle)
       target_rank
              - rank of target (non-negative integer)
       target_disp
              -  displacement  from  start  of window to beginning of target buffer (non-negative
              integer)
       target_count
              - number of entries in target buffer (non-negative integer)
       target_datatype
              - datatype of each entry in target buffer (handle)
       op     - reduce operation (handle)
       win    - window object (handle)

OUTPUT PARAMETERS

       result_addr
              - initial address of result buffer (choice)
       request
              - RMA request (handle)

NOTES

       This operations is atomic with respect to other "accumulate" operations.

       The get and accumulate steps are  executed  atomically  for  each  basic  element  in  the
       datatype  (see  MPI  3.0  Section  11.7 for details). The predefined operation MPI_REPLACE
       provides fetch-and-set behavior.

       The basic components of both the origin and target datatype must be  the  same  predefined
       datatype (e.g., all MPI_INT or all MPI_DOUBLE_PRECISION ).

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.

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  guarantee 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_ARG
              - Invalid argument.  Some argument is invalid and is not identified by  a  specific
              error class (e.g., MPI_ERR_RANK ).
       MPI_ERR_BUFFER
              - Invalid buffer pointer.  Usually a null buffer where one is not valid.
       MPI_ERR_COUNT
              - Invalid count argument.  Count arguments must be non-negative; a count of zero is
              often valid.
       MPI_ERR_DISP
              -
       MPI_ERR_RANK
              - Invalid source or destination rank.  Ranks must be between zero and the  size  of
              the  communicator  minus  one;  ranks  in  a  receive  (  MPI_Recv  ,  MPI_Irecv  ,
              MPI_Sendrecv , etc.) may also be MPI_ANY_SOURCE .

       MPI_ERR_TYPE
              - Invalid datatype argument.  Additionally, this error can occur if an  uncommitted
              MPI_Datatype (see MPI_Type_commit ) is used in a communication call.
       MPI_ERR_WIN
              - Invalid MPI window object
       MPI_ERR_OTHER
              - Other error; use MPI_Error_string to get more information about this error code.

SEE ALSO

       MPI_Get_accumulate MPI_Fetch_and_op

                                             2/9/2024                      MPI_Rget_accumulate(3)