MPI_Send function - Message Passing Interface (original) (raw)

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

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