aeron-client/src/main/java/io/aeron/Publication.java
public final long offer(
        final DirectBuffer bufferOne,
        final int offsetOne,
        final int lengthOne,
        final DirectBuffer bufferTwo,
        final int offsetTwo,
        final int lengthTwo)
    {
        return offer(bufferOne, offsetOne, lengthOne, bufferTwo, offsetTwo, lengthTwo, null);
    }
public final long offer(
        final DirectBuffer bufferOne,
        final int offsetOne,
        final int lengthOne,
        final DirectBuffer bufferTwo,
        final int offsetTwo,
        final int lengthTwo)
    {
        return offer(bufferOne, offsetOne, lengthOne, bufferTwo, offsetTwo, lengthTwo, null);
    }
Non-blocking publish of a message composed of two parts, e.g. a header and encapsulated payload.

@param bufferOne containing the first part of the message.
@param offsetOne at which the first part of the message begins.
@param lengthOne of the first part of the message.
@param bufferTwo containing the second part of the message.
@param offsetTwo at which the second part of the message begins.
@param lengthTwo of the second part of the message.
@return The new stream position, otherwise a negative error value of {@link #NOT_CONNECTED},
{@link #BACK_PRESSURED}, {@link #ADMIN_ACTION}, {@link #CLOSED}, or {@link #MAX_POSITION_EXCEEDED}.