Ubuntu :: Serial Port Read, Write After DTR Toggle In C++?

I need to read and write to a serial device. When I connect via gtkterm, I need to toggle DTR before I can communicate with the device . My problem is that I cannot emulate this in C++.

I want to write some code that can setup a comport, toggle the DTR, then read and write strings to the port. However all my attempts have been fruitless. My serial settings are B9600, No parity, no hardware control, 8 bt characters and 1 stop bit:

Code:
#include <iostream>
#include <SerialStream.h>
#include <sys/ioctl.h>
#include <fcntl.h>
using namespace LibSerial;

[Code]...