1. In a file contains the line “I am a boy\r\n” then on reading this line into the array str using fgets(). What will str contain?
A. “I am a boy\r\n\0”
B. “I am a boy\r\0”
C. “I am a boy\n\0”
D. “I am a boy”
Answer: Option C
Declaration: char *fgets(char *s, int n, FILE *stream);
fgets reads characters from stream into the string s. It stops when it reads either n – 1 characters or a newline character, whichever comes first.
Therefore, the string str contain “I am a boy\n\0”
2. What is the purpose of “rb” in fopen() function used below in the code?
fp = fopen(“source.txt”, “rb”);
A. open “source.txt” in binary mode for reading
B. open “source.txt” in binary mode for reading and writing
C. Create a new file “source.txt” for reading and writing
D. None of above
Answer: Option A
The file source.txt will be opened in the binary mode.
3. What does fp point to in the program ?
A. The first character in the file
B. A structure which contains a char pointer which points to the first character of a file.
C. The name of the file.
D. The last character in the file.
Answer: Option B
The fp is a structure which contains a char pointer which points to the first character of a file.
4. Which of the following operations can be performed on the file “NOTES.TXT” using the below code?
fp = fopen(“NOTES.TXT”, “r+”);
D. Read and Write
Answer: Option D
r+ Open an existing file for update (reading and writing).
5. To print out a and b given below, which of the following printf() statement will you use?
A. printf(“%f %lf”, a, b);
B. printf(“%Lf %f”, a, b);
C. printf(“%Lf %Lf”, a, b);
D. printf(“%f %Lf”, a, b);
Answer: Option A
To print a float value, %f is used as format specifier.
To print a double value, %lf is used as format specifier.
Therefore, the answer is printf(“%f %lf”, a, b);