Need help setting up a serial port connection

[jvwlong]

Hello, I am trying to wrtie a program in Ubuntu where, throught the console, I can read and write a serial port. So I have started using the qextserialport library. I found code online and tried to emulate it to make a simple test to see if I can get the program to merely connect to the serial port. But alas my program does not seem to be connecting. And I am at a loss for why it won't open the port. Here is my code

#include <QtCore/QCoreApplication>
#include <3rdparty/qextserialport/src/qextserialport.h>
#include <iostream>
#include <qiodevice.h>
using namespace std;
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    const char data[]= "e";
    QextSerialPort * port = new QextSerialPort("/dev/ttyUSB0");
       port->setBaudRate(BAUD115200);
       port->setFlowControl(FLOW_OFF);
       port->setParity(PAR_NONE);
       port->setDataBits(DATA_8);
       port->setStopBits(STOP_1);
       port->setTimeout(10);
       bool res = false;
       res = port->open(QIODevice::ReadWrite | QIODevice::Unbuffered);
 
       if(res)
          {
              cout << "Opened" << endl;
              char i = port->write(data);
          }
          else
          {
              cout << "Failed to connect" << endl;
          }
          return a.exec();
       }

#include <QtCore/QCoreApplication>
#include <3rdparty/qextserialport/src/qextserialport.h>
#include <iostream>
#include <qiodevice.h>
using namespace std;
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    const char data[]= "e";
    QextSerialPort * port = new QextSerialPort("/dev/ttyUSB0");
       port->setBaudRate(BAUD115200);
       port->setFlowControl(FLOW_OFF);
       port->setParity(PAR_NONE);
       port->setDataBits(DATA_8);
       port->setStopBits(STOP_1);
       port->setTimeout(10);
       bool res = false;
       res = port->open(QIODevice::ReadWrite | QIODevice::Unbuffered);

       if(res)
          {
              cout << "Opened" << endl;
              char i = port->write(data);
          }
          else
          {
              cout << "Failed to connect" << endl;
          }
          return a.exec();
       }

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The console that is opened always displays "Failed to connect"
Can anyone see any very obvious erros?

Thanks
-Jvwlong

[Lesiok]

Do You have rigths to use /dev/ttyUSB0 ?

[jvwlong]

I believe I do? How would I check if I have permission or not?

[Lesiok]

I believe I do? How would I check if I have permission or not?

From command line :

ls -l /dev/ttyUSB0

and watch at screen.

[jvwlong]

This is the output from that command
"crw-rw---- 1 root dialout 188, 0 Jul 2 09:30 /dev/ttyUSB0"

[jvwlong]

Solved. I just needed to be added to the dialout group.