driver-core/src/main/com/mongodb/internal/connection/RequestMessage.java
protected void writeMessagePrologue(final BsonOutput bsonOutput) {
        bsonOutput.writeInt32(0); // length: will set this later
        bsonOutput.writeInt32(id);
        bsonOutput.writeInt32(0); // response to
        bsonOutput.writeInt32(opCode.getValue());
    }
protected void writeMessagePrologue(final BsonOutput bsonOutput) {
        bsonOutput.writeInt32(0); // length: will set this later
        bsonOutput.writeInt32(id);
        bsonOutput.writeInt32(0); // response to
        bsonOutput.writeInt32(opCode.getValue());
    }
Writes the message prologue to the given output.

@param bsonOutput the output