MPI_SENDRECV, MPI_Sendrecv

Purpose

Performs a blocking send and receive operation.

C synopsis

#include <mpi.h>
int MPI_Sendrecv(void *sendbuf,int sendcount,MPI_Datatype sendtype,
                 int dest,int sendtag,void *recvbuf,int recvcount,
                 MPI_Datatype recvtype,int source,int recvtag,
                 MPI_Comm comm,MPI_Status *status);

C++ synopsis

#include mpi.h
void MPI::Comm::Sendrecv(const void* sendbuf, int sendcount,
                         const MPI::Datatype& sendtype, int dest,
                         int sendtag, void* recvbuf, int recvcount,
                         const MPI::Datatype& recvtype, int source,
                         int recvtag) const;

#include mpi.h
void MPI::Comm::Sendrecv(const void* sendbuf, int sendcount,
                         const MPI::Datatype& sendtype, int dest,
                         int sendtag, void* recvbuf, int recvcount,
                         const MPI::Datatype& recvtype, int source,
                         int recvtag, MPI::Status& status)
                         const;

FORTRAN synopsis

include 'mpif.h' or use mpi
MPI_SENDRECV(CHOICE SENDBUF,INTEGER SENDCOUNT,INTEGER SENDTYPE,
      INTEGER DEST,INTEGER SENDTAG,CHOICE RECVBUF,INTEGER RECVCOUNT,
      INTEGER RECVTYPE,INTEGER SOURCE,INTEGER RECVTAG,INTEGER COMM,
      INTEGER STATUS(MPI_STATUS_SIZE),INTEGER IERROR)

Parameters

sendbuf
     is the initial address of the send buffer (choice) (IN)

sendcount
     is the number of elements to be sent (integer) (IN)

sendtype
     is the type of elements in the send buffer (handle) (IN)

dest
     is the rank of the destination task (integer) (IN)

sendtag
     is the send tag (integer) (IN)

recvbuf
     is the initial address of the receive buffer (choice) (OUT)

recvcount
     is the number of elements to be received (integer) (IN)

recvtype
     is the type of elements in the receive buffer (handle) (IN)

source
     is the rank of the source task or MPI_ANY_SOURCE (integer) (IN)

recvtag
     is the receive tag or MPI_ANY_TAG (integer) (IN)

comm
     is the communicator (handle) (IN)

status
     is the status object (Status) (INOUT). Note that in FORTRAN a single
     status object is an array of integers.

IERROR
     is the FORTRAN return code. It is always the last argument.

Description

This subroutine is a blocking send and receive operation. Send and receive
use the same communicator but can use different tags. The send and the
receive buffers must be disjoint and can have different lengths and
datatypes.

Passing MPI_STATUS_IGNORE for the status argument causes PE MPI to skip
filling in the status fields. By passing this value for status, you can
avoid having to allocate a status object in programs that do not need to
examine the status fields.

Errors

Invalid count(s)
     count < 0

Invalid datatype(s)

Type not committed

Invalid destination
     dest < 0 or dest > = groupsize

Invalid source
     source < 0 or source > = groupsize

Invalid communicator

Invalid tag(s)
     tag < 0

Invalid status ignore value

MPI not initialized

MPI already finalized

Related information

     MPI_RECV
     MPI_SEND