QTextStream stdin readline not pausing for input

Question

Here is a very simple application to illustrate the problem I am having.

#include <QTextStream>

int main()
{
    QTextStream cin(stdin);
    QTextStream cout(stdout);

    QString test;

    cout << "Enter a value: ";
    cout.flush();
    cin >> test;

    cout << "Enter another value: ";
    cout.flush();

    test = cin.readLine();
    cout << test;
    return 0;
}

I expect execution to pause and wait for input at test = cin.readline();, but it does not. If I remove cin >> test; then it pauses.

Why is this code behaving like this and how do I get behaviour I want?

Answer 1

Probably the buffer still has a endline character '\n' that is accepted by cin.readLine(); - try flushing it with cin.flush() before executing cin.readLine().

---

This code is working:

QTextStream cin(stdin);
QTextStream cout(stdout);

QString test;

cout << "Enter a value: ";
cout.flush();
cin >> test;

cout << "Enter another value: ";
cout.flush();
cin.skipWhiteSpace(); //Important line!
test = cin.readLine();
cout << test;
return 0;

You just need to add cin.skipWhiteSpace() before cin.readLine(), as I said before the '\n' character is still in buffer and that method is getting rid of it.