CODE EXAMPLE FOR CPP

I/O Redirection in C++

// Cpp program to redirect cout to a file
#include <fstream>
#include <iostream>
#include <string>
 
using namespace std;
 
int main()
{
    fstream file;
    file.open("cout.txt", ios::out);
    string line;
 
    // Backup streambuffers of  cout
    streambuf* stream_buffer_cout = cout.rdbuf();
    streambuf* stream_buffer_cin = cin.rdbuf();
 
    // Get the streambuffer of the file
    streambuf* stream_buffer_file = file.rdbuf();
 
    // Redirect cout to file
    cout.rdbuf(stream_buffer_file);
 
    cout << "This line written to file" << endl;
 
    // Redirect cout back to screen
    cout.rdbuf(stream_buffer_cout);
    cout << "This line is written to screen" << endl;
 
    file.close();
    return 0;
}