trusty (3) MPI_Put.openmpi.3.gz

Provided by: openmpi-doc_1.6.5-8_all bug

NAME

       MPI_Put - Copies data from the origin memory to the target.

SYNTAX

C Syntax

       #include <mpi.h>
       MPI_Put(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)

Fortran Syntax (see FORTRAN 77 NOTES)

       INCLUDE 'mpif.h'
       MPI_PUT(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

C++ Syntax

       #include <mpi.h>
       void MPI::Win::Put(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 start of window to target buffer (nonnegative integer).

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

       target_datatype
                 Data type of each entry in target buffer (handle).

       win       Window object used for communication (handle).

OUTPUT PARAMETER

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       MPI_Put  transfers  origin_count successive entries of the type specified by origin_datatype, starting at
       address origin_addr on the origin node to the target node specified by the  win,  target_rank  pair.  The
       data  are  written  in  the target buffer at address target_addr = window_base + target_disp x disp_unit,
       where window_base and disp_unit are the base address and window displacement  unit  specified  at  window
       initialization, by the target process.

       The target buffer is specified by the arguments target_count and target_datatype.

       The  data  transfer is the same as that which would occur if the origin process executed a send operation
       with arguments origin_addr, origin_count, origin_datatype, target_rank, tag, comm, and the target process
       executed  a  receive  operation  with  arguments target_addr, target_count, target_datatype, source, tag,
       comm, where target_addr is the target  buffer  address  computed  as  explained  above,  and  comm  is  a
       communicator for the group of win.

       The  communication  must satisfy the same constraints as for a similar message-passing communication. The
       target_datatype may not specify overlapping entries in the target buffer.  The  message  sent  must  fit,
       without  truncation,  in the target buffer. Furthermore, the target buffer must fit in the target window.
       In addition, only processes within the same buffer can access the target window.

       The target_datatype argument is a handle to a datatype object defined at  the  origin  process.  However,
       this  object  is  interpreted at the target process: The outcome is as if the target datatype object were
       defined at the target process, by the same sequence of calls used to define it at the origin process. The
       target data type must contain only relative displacements, not absolute addresses. The same holds for get
       and accumulate.

NOTES

       The target_datatype argument is a handle to a datatype object that is defined at the origin process, even
       though  it  defines  a  data  layout  in  the  target  process  memory. This does not cause problems in a
       homogeneous or heterogeneous environment, as long as only portable data types  are  used  (portable  data
       types are defined in Section 2.4 of the MPI-2 Standard).

       The  performance  of  a  put  transfer can be significantly affected, on some systems, from the choice of
       window location and the shape and location of the origin and target buffer: Transfers to a target  window
       in  memory  allocated  by  MPI_Alloc_mem  may  be  much  faster  on shared memory systems; transfers from
       contiguous buffers will be faster on most, if not  all,  systems;  the  alignment  of  the  communication
       buffers may also impact performance.

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_Get
       MPI_Accumulate