C Programming Online Test

1. Select the correct declaration of setjmp().

2. A variable declared in a function can be used in main().

3. The following C code results in an error. State whether true or false.

#include<stdio.h>
#include<time.h>
int main()
{
    struct tm *local;
    time_t t;
    t=time(NULL);
    local=asctime(localtime(&t));
    printf("%d",local->tm_wday);
    return 0;
}

4. If the user enters 1 3.2 s, what value will be returned by the scanf()?

scanf("%d %f %c", &s1, &s2, &s3);

5. Loss in precision occurs for typecasting from____________

6. What will be the output of the following C code?

    #include <stdio.h>
    struct temp
    {
        int a;
    } s;
    void change(struct temp);
    main()
    {
        s.a = 10;
        change(s);
        printf("%d\n", s.a);
    }
    void change(struct temp s)
    {
        s.a = 1;
    } 

7. HUGE_VAL macro is used when the output of the function may not be ___________

8. What will be the output of the following C statement?

int ungetc(int c, FILE *fp)

9. What will be the output of the following C code?

    #include <stdio.h>
    struct point
    {
        int x;
        int y;
    };
    void foo(struct point*);
    int main()
    {
        struct point p1[] = {1, 2, 3, 4, 5};
        foo(p1);
    }
    void foo(struct point p[])
    {
        printf("%d %d\n", p->x, (p + 2)->y);
    } 

10. When the pointer is NULL, then the function realloc is equivalent to the function ___________

11. What will be the output of the following C code?

    #include <stdio.h>
    typedef struct p
    {
        int x, y;
    }k = {1, 2};
    int main()
    {
        p k1 = k;
        printf("%d\n", k1.x);
    } 

12. Which macro can be used to detect and report exceptional conditions?

13. What is the type declared by the header file signal.h?

14. log(x) function defined in math.h header file is __________

15. User-defined data type can be derived by___________

16. What will be the output of the following C code?

    #include <stdio.h>
    int main()
    {
        int i = 0;
        while (i < 2)
        {
            if (i == 1)
                break;
                i++;
                if (i == 1)
                    continue;
                    printf("In while loop\n");
        }
        printf("After loop\n");
    } 

17. What is the difference between %e and %g?

18. What will be the output of the following C code?

    #include <stdio.h>
    int main()
    {
        if (~0 == 1)
            printf("yes\n");
        else
            printf("no\n");
    } 

19. In linux, apart from including math header file, the program is successfully executed by which of the following?

20. What is the first argument in command line arguments?

21. If the file name is enclosed in double quotation marks, then _________

22. What will be the output of the following C code?

    #include <stdio.h>
    union u
    {
        struct p
        {
            unsigned char x : 2;
            unsigned int y : 2;
        };
        int x;
    };
    int main()
    {
        union u u;
        u.p.x = 2;
        printf("%d\n", u.p.x);
    } 

23. Comment on the output of the following C code.

    #include <stdio.h>
    int main()
    {
        int i, n, a = 4;
        scanf("%d", &n);
        for (i = 0; i < n; i++)
            a = a * 2;
    } 

24. Property of the external variable to be accessed by any source file is called by the C90 standard as __________

25. What will be the output of the following C code?

    #include <stdio.h>
    int main()
    {
        char *str = "hello world";
        char strc[] = "good morning india\n";
        strcpy(strc, str);
        printf("%s\n", strc);
        return 0;
    } 

26. What will be the output of the following C code?

void *memset(void *c, int c, size-t n) 
unsigned char ch = c;
unsigned char *su;
for (su = s; 0 < n; ++su, --n)
<br>
*su = ch;
<br>

27. Which of the following is not an example of big endian machines?

28. What is the return value of getc()?

29. What will be the output of the following C code?

    #include <stdio.h>
    int *i;
    int main()
    {
        if (i == 0)
            printf("true\n");
        return 0;
    } 

30. What will be the output of the following C code?

    #include <stdio.h>
    void main()
    {
        int k = 0;
        double b = k++ + ++k + k--;
        printf("%d", k);
    } 

31. What will be the output of the following C code?

    #include <stdio.h>
    int main()
    {
        int i = 1;
        if (i++ && (i == 1))
            printf("Yes\n");
        else
            printf("No\n");
    } 

32. What will be the output of the following C code?

    #include <stdio.h>
    int *f();
    int main()
    {
        int *p = f();
        printf("%d\n", *p);
    }
    int *f()
    {
        int j = 10;
        return &j;
    }

33. How many times while loop condition is tested in the following C code snippets, if i is initialized to 0 in both the cases?

while (i < n)
         i++;
    ————-
    do
         i++;
    while (i <= n);

34. What will be the output of the following C code?

    #include<stdio.h>
    int main()
    {
        int a = 1, b = 2, c = 3, d = 4, e;
        e = c + d = b * a;
        printf("%d, %d\n", e, d);
    } 

35. Which of the given statement is not true with respect to void longjmp( jmp-buf env, int val)?

36. What will be the output for the given code printf(“\n The number is %07d”,1212);

37. Comment on the following 2 arrays with respect to P and Q.

   int *a1[8];
   int *(a2[8]);
   P. Array of pointers
   Q. Pointer to an array

38. What is the problem in the following C declarations?

   int func(int);
   double func(int);
   int func(float);

39. Which function will return the current file position for stream?

40. What will be the output of the following C code?

#define display(a) #a
main()
{
    printf(display("56#7"));
}

41. What will be the output of the following C code?

    #include <stdio.h>
    double var = 8;
    int main()
    {
        int var = 5;
        printf("%d", var);
    }

42. What will be the output of the following C code?

    #include <stdio.h>
    int *f();
    int main()
    {
        int *p = f();
        printf("%d\n", *p);
    }
    int *f()
    {
        int *j = (int*)malloc(sizeof(int));
        *j = 10;
        return j;
    }

43. What will be the output of the following C code? (Assuming that we have entered the value 1 in the standard input)

    #include <stdio.h>
    void main()
    {
        int ch;
        printf("enter a value between 1 to 2:");
        scanf("%d", &ch);
        switch (ch, ch + 1)
        {
           case 1:
              printf("1\n");
              break;
           case 2:
              printf("2");
              break;
        }
    } 

44. What are the first and second arguments of fopen?

45. Point out the error (if any) in the following C code?

#include <stdlib.h>
#include <stdio.h>
int main(void)
{
    int* p = NULL;
    struct S *s = NULL;
    void(*f)(int, double) = NULL;
    char *ptr = malloc(15);
    if (ptr == NULL) printf("Out of memory");
    free(ptr);
}

46. What will be the output of the following C code?

    #include <stdio.h>
    int main()
    {
        int i = 10;
        int *const p = &i;
        foo(&p);
        printf("%d\n", *p);
    }
    void foo(int **p)
    {
        int j = 11;
        *p = &j;
        printf("%d\n", **p);
    } 

47. What will be the output of the following C code?

    #include <stdio.h>
    int const print()
    {
        printf("Sanfoundry.com");
        return 0;
    }
    void main()
    {
        print();
    }

48. Which of the following macros is defined under the header limits.h?

49. setvbuf() and setbuf() function controls buffering for the stream.

50. What will be the output of the following C code?

    #include <stdio.h>
    void f(int);
    void (*foo)(float) = f;
    int main()
    {
        foo(10);
    }
    void f(int i)
    {
        printf("%d\n", i);
    }