File Input Output MCQs

Question 1

On freeing a dynamic memory, if the pointer value is not modified, then the pointer points to.

Accepted Answer

The same deallocated memory location

Answer

Other dynamically allocated memory

Answer

It points back to the location it was initialized with

Question 2

void * malloc(size_t n) returns?

Accepted Answer

Pointer to n bytes of uninitialized storage

Answer

NULL if the request can be satisfied

Answer

Nothing

Answer

None of the mentioned

Question 3

What does the following segment of C code do? fprintf(fp, "Copying!");

Accepted Answer

It writes "Copying!" into the file pointed by fp

Answer

It reads "Copying!" from the file and prints on display

Answer

It writes as well as reads "Copying!" to and from the file and prints it

Answer

None of the mentioned

Question 4

Which of the following represents the function for scanf()?

Accepted Answer

int scanf(char *format, ...)

Answer

void scanf(char *format, ...)

Answer

char scanf(int format, ...)

Answer

char *scanf(char *format, ...)

Question 5

Which of the following can be used for random number generation?

Accepted Answer

random()

Answer

rnd()

Answer

rndm()

Answer

none of the mentioned

Question 6

What will be the output of the following C code? #include <stdio.h> int main() { char *s = "myworld"; int i = 9; printf("%*s", i, s); }

Accepted Answer

myworld(note: spaces to the left of myworld)

Answer

myworld

Answer

myworld (note:followed by two spaces after myworld)

Answer

Undefined

Question 7

What will be the output of the following C statement? fprintf(stderr, "error: could not open filen");

Accepted Answer

The diagnostic output is directly displayed in the output

Answer

The diagnostic output is pipelined to the output file

Answer

The line which caused error is compiled again

Answer

The program is immediately aborted

Question 8

Which among the following is the odd one out?

Accepted Answer

scanf

Answer

printf

Answer

fprintf

Answer

putchar

Question 9

The syntax of the scanf() is scanf("control string ", arg1,arg2,arg3,....,argn); the prototype of control string is

Accepted Answer

[=%[width][modifiers]type=]

Answer

[=%[modifiers][width]type=]

Answer

[=%[width] [modifiers]]

Answer

[width][modifiers]