NAME

       MPI_Rsend - Ready send.

SYNTAX

C Syntax

       #include <mpi.h>
       int MPI_Rsend(const void *buf, int count, MPI_Datatype datatype, int dest,
            int tag, MPI_Comm comm)

Fortran Syntax

       USE MPI
       ! or the older form: INCLUDE 'mpif.h'
       MPI_RSEND(BUF, COUNT, DATATYPE, DEST, TAG, COMM, IERROR)
            <type>    BUF(*)
            INTEGER   COUNT, DATATYPE, DEST, TAG, COMM, IERROR

Fortran 2008 Syntax

       USE mpi_f08
       MPI_Rsend(buf, count, datatype, dest, tag, comm, ierror)
            TYPE(*), DIMENSION(..), INTENT(IN) :: buf
            INTEGER, INTENT(IN) :: count, dest, tag
            TYPE(MPI_Datatype), INTENT(IN) :: datatype
            TYPE(MPI_Comm), INTENT(IN) :: comm
            INTEGER, OPTIONAL, INTENT(OUT) :: ierror

C++ Syntax

       #include <mpi.h>
       void Comm::Rsend(const void* buf, int count, const Datatype&
            datatype, int dest, int tag) const

INPUT PARAMETERS

       buf       Initial address of send buffer (choice).

       count     Number of elements in send buffer (nonnegative integer).

       datatype  Datatype of each send buffer element (handle).

       dest      Rank of destination (integer).

       tag       Message tag (integer).

       comm      Communicator (handle).

OUTPUT PARAMETER

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       A  ready  send  may  only  be called if the user can guarantee that a receive is already posted. It is an
       error if the receive is not posted before the ready send is called.

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.

4.1.6                                             Sep 30, 2023                                      MPI_Rsend(3)