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

Initiates a standard mode send operation and returns a handle to the requested communication operation.

Syntax

int MPIAPI MPI_Isend(
  _In_opt_ void         *buf,
           int          count,
           MPI_Datatype datatype,
           int          dest,
           int          tag,
           MPI_Comm     comm,
  _Out_    MPI_Request  *request
);

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.
request [out]
On return, contains a handle to the requested communication operation.

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

This function is local, it returns immediately, and does not wait for any other process. This function can return before the message is copied out of the send buffer.

Requirements