Can't end while loop: while(getline(cin, str))

I redirected the cin to a .txt file, and I tried to read line by line in the txt file with using while(getline(cin,str)).But i found that the while loop just keeps running and never ends, so what should I do?

I redirected cin and cout through the "run configuration" in eclipse:

My code is:

#include <iostream>
using namespace std;

int main() {
    string line;
    while(getline(cin, line)){
        cout << line << endl;
    }
    cout << "hello" << endl;
    return 0;
}

The problem is I can't get hello in the output.