File Streams and String Streams CPP MCQ

1. Which operator is used to insert the data into file?
a) >>
b) <<
c) <
d) None of the mentioned


2. Which function is used to position back from the end of file object?
a) seekg
b) seekp
c) Both a & b
d) None of the mentioned


3. How many number of objects are used for input and output to a string?
a) 1
b) 2
c) 3
d) 4


4. What is the output of this program?

1.     #include <iostream>

2.     #include <fstream>

3.     using namespace std;

4.     int main () 

5.     {

6.         int length;

7.         char * buffer;

8.         ifstream is;

9.         is.open ("sample.txt", ios :: binary );

10.         is.seekg (0, ios :: end);

11.         length = is.tellg();

12.         is.seekg (0, ios :: beg);

13.         buffer = new char [length];

14.         is.read (buffer, length);

15.         is.close();

16.         cout.write (buffer, length);

17.         delete[] buffer;

18.         return 0;

19.     }

a) This is sample
b) sample
c) Error
d) Runtime error


5. What is the output of this program?

1.     #include <iostream>

2.     using namespace std;

3.     int main ()

4.     {

5.         char first, second;

6.         cout << "Enter a word: ";

7.         first = cin.get();

8.         cin.sync();

9.         second = cin.get();

10.         cout << first << endl;

11.         cout << second << endl;

12.         return 0;

13.     }

a) first
b) second
c) Returns first 2 letter or number from the entered word
d) None of the mentioned


6. What is the output of this program?

1.     #include<iostream>

2.     #include <fstream>

3.     using namespace std;

4.     int main () 

5.     {

6.         ofstream outfile ("test.txt");

7.         for (int n = 0; n < 100; n++)

8.         {

9.             outfile << n;

10.             outfile.flush();

11.         }

12.         cout << "Done";

13.         outfile.close();

14.         return 0;

15.     }

a) Done
b) Error
c) Runtime error
d) None of the mentioned


7. What is the output of this program?

1.     #include <iostream>

2.     using namespace std;

3.     int main ()

4.     {

5.         int a = 100;

6.         double b = 3.14;

7.         cout << a;

8.         cout << endl;

9.         cout << b << endl << a * b;

10.         endl (cout);

11.         return 0;

12.     }

a) 100
b) 3.14
c) 314
d) All of the mentioned


8. By seeing which operator thus this program stops getting the input?

1.     #include <iostream>

2.     #include <fstream>

3.     using namespace std;

4.     int main ()

5.     {

6.         char ch;

7.         streambuf * p;

8.         ofstream os ("test.txt");

9.         pbuf = os.rdbuf();

10.         do {

11.             ch = cin.get();

12.             p -> sputc(ch);

13.         } while (ch != '.');

14.         os.close();

15.         return 0;

16.     }

a) dot operator
b) insertion operator
c) $ symbol
d) None of the mentioned


9. Which member function is used to determine whether the stream object is currently associated with a file?
a) is_open
b) buf
c) string
d) None of the mentioned


10. Which header file is used for reading and writing to a file?
a) #include<iostream>
b) #include<fstream>
c) #include<file>
d) None of the mentioned