File Handling Interview Questions

    Question 1: C++ File Stream Declaration

    Which header file is required for file handling in C++?

    Question 2: C++ File Modes

    Which mode is used to append data at the end of a file in C++?

    Question 3: C++ Guess the Output – Writing File

    What will this program do?

    #include <iostream>
#include <fstream>
using namespace std;

int main() {
    ofstream file("test.txt");
    file << "Hello File";
    file.close();
    return 0;
}

    Question 4: C++ File Reading

    Which class is used to read from a file in C++?

    Question 5: C++ Guess the Output – Reading File

    Suppose "data.txt" contains 1234. What will this program print?

    #include <iostream>
#include <fstream>
using namespace std;

int main() {
    ifstream file("data.txt");
    int x;
    file >> x;
    cout << x;
    file.close();
    return 0;
}

    Question 6: C++ File Opening Multiple Modes

    Which of the following opens a file for both reading and writing?

    Question 7: C++ Guess the Output – Appending File

    What will happen when this program runs?

    #include <iostream>
#include <fstream>
using namespace std;

int main() {
    ofstream file("log.txt", ios::app);
    file << "New Entry\n";
    file.close();
    return 0;
}

    Question 8: C++ Binary File Mode

    Which flag is used to open a file in binary mode?

    Question 9: C++ Guess the Output – getline from File

    Suppose "note.txt" contains:
    C++ is fun!
    What will this program print?

    #include <iostream>
#include <fstream>
using namespace std;

int main() {
    ifstream file("note.txt");
    string line;
    getline(file, line);
    cout << line;
    return 0;
}

    Question 10: C++ Closing File

    Why is file.close() used in C++?