C#

private void button2_Click(object sender, RoutedEventArgs e)
        {

            Thread Runst = new Thread(Run);
            Runst.Start();           
            
        }

        public void Run()
        {
            ProcessStartInfo processStartInfo = new ProcessStartInfo("C:\\test.exe");
            processStartInfo.ErrorDialog = false;
            processStartInfo.UseShellExecute = false;
            processStartInfo.RedirectStandardError = true;
            processStartInfo.RedirectStandardInput = true;
            processStartInfo.RedirectStandardOutput = true;            
            //processStartInfo.CreateNoWindow = true; //no console window



            Process process = new Process();
            process.StartInfo = processStartInfo;
            bool processStarted = process.Start();

            while (!process.StandardOutput.EndOfStream)
            {
                
                textBox2.Dispatcher.Invoke(DispatcherPriority.Normal, (Action)delegate()
                {
                    textBox2.Text += process.StandardOutput.ReadLine() + Environment.NewLine;
                                        
                });
                
            }
                
                
        }

#include <stdio.h>
#include <windows.h>


int main()
{
	for (int i=0;i<=30;i++)
	{
	fprintf(stdout,"%d) This is NORMALL stout (0-30)\n",i);		
	Sleep(100);
	}

	/*for (int i=30;i<=60;i++)
	{
	fprintf(stderr,"%d) This is ERROR stout (30-60)\n",i);		
	Sleep(100);
	}*/		
}

process.OutputDataReceived += new DataReceivedEventHandler(CatchOutHandler);

bool stdReading;
StreamReader stdout;
StreamReader stderr;

public void LaunchProcess() {
	ProcessStartInfo psi=new ProcessStartInfo();
	psi....
	log("Starting process");
	Process p=Process.Start(psi);
	stdout=p.StandardOutput;
	stderr=p.StandardError;
	stdReading=true;
	Thread outThread=new Thread(new ThreadStart(outReader));
	outThread.Start();
	Thread errThread=new Thread(new ThreadStart(errReader));
	errThread.Start();
	p.WaitForExit();
	log("Process is done");
	Thread.Sleep(300);  // allow some time for streams to settle
	stdReading=false;
	errThread.Join(300);
	outThread.Join(300);
	log("Reading streams in done");
}
public void outReader() {
	int DIM=1024;
	char[] buf=new char[DIM];
	while (stdReading) {
		int count=stdout.Read(buf, 0, DIM);
		// now process count characters in buf
		string s=new string(buf, 0, count);
		...
	}
}
public void errReader() {
	int DIM=1024;
	char[] buf=new char[DIM];
	while (stdReading) {
		int count=stdout.Read(buf, 0, DIM);
		// now process count characters in buf
		string s=new string(buf, 0, count);
		...
	}
}