MPI_Send function

Performs a standard mode send operation and returns when the send buffer can be safely reused.

Syntax

int MPIAPI MPI_Send(
  _In_opt_ void         *buf,
           int          count,
           MPI_Datatype datatype,
           int          dest,
           int          tag,
           MPI_Comm     comm
);

Parameters

• buf [in, optional]
  A pointer to the buffer that contains the data to be sent.

• count
  The number of elements in the buffer. If the data part of the message is empty, set the count parameter to 0.

• datatype
  The data type of the elements in the buffer.

• dest
  The rank of the destination process within the communicator that is specified by the comm parameter.

• tag
  The message tag that can be used to distinguish different types of messages.

• comm
  The handle to the communicator.

Return value

Returns MPI_SUCCESS on success. Otherwise, the return value is an error code.

In Fortran, the return value is stored in the IERROR parameter.

Fortran

    MPI_SEND(BUF, COUNT, DATATYPE, DEST, TAG, COMM, IERROR)
        <type> BUF(*)
        INTEGER COUNT, DATATYPE, DEST, TAG, COMM, IERROR

Remarks

This function is non-local. Successful completion might depend on the existence of a matching receive function.

This function can return before a matching receive function is invoked if the MPI implementation buffers the message. However, buffer space might be unavailable, or outgoing messages might not be buffered for performance reasons. If the message is not buffered, the function does not return until the data has been moved to the receiving process.

This function can be called whether or not a matching receive function is posted. It might finish before a matching receive function is posted.

Requirements

See also

MPI Point to Point Functions

MPI_Bsend

MPI_Rsend

MPI_Ssend

MPI_Recv