C Interview Questions EXAMPLES

1. What is C language ?
   
   
2. What does static variable mean?
   
   
3. What are the different storage classes in C ?
   
   
4. What is hashing ?
   
   
5. Can static variables be declared in a header file ?
   
   
6. Can a variable be both constant and volatile ?
   
   
7. Can include files be nested?
   
   
8. What is a null pointer ?
   
   
9. What is the output of printf("%d") ?
   
   
10. What is the difference between calloc() and malloc() ?
    
    
11. What is the difference between printf() and sprintf() ?
    
    
12. How to reduce a final size of executable ?
    
    
13. Can you tell me how to check whether a linked list is circular ?
    
    
14. Advantages of a macro over a function ? 
    
    
15. What is the difference between strings and character arrays ?
    
    
16. Write down the equivalent pointer expression for referring the same element a[i][j][k][l] ?
    
    
17. Which bit wise operator is suitable for checking whether a particular bit is on or off ?
    
    
18. Which bit wise operator is suitable for turning off a particular bit in a number ?
    
    
19. Which bit wise operator is suitable for putting on a particular bit in a number ?
    
    
20. Does there exist any other function which can be used to convert an integer or a float to a string ?
    
    
21. Why does malloc(0) return valid memory address ? What's the use ?
    
    
22. Difference between const char* p and char const* p 
    
    
23. What is the result of using Option Explicit ?
    
    
24. What is the benefit of using an enum rather than a #define constant ?
    
    
25. What is the quickest sorting method to use ?
    
    
26. When should the volatile modifier be used ?
    
    
27. When should the register modifier be used? Does it really help ?
    
    
28. How can you determine the size of an allocated portion of memory ?
    
    
29. What is page thrashing ?
    
    
30. When does the compiler not implicitly generate the address of the first element of an array ?
    
    
31. What is the benefit of using #define to declare a constant ?
    
    
32. How can I search for data in a linked list ?
    
    
33. Why should we assign NULL to the elements (pointer) after freeing them ?
    
    
34. What is a null pointer assignment error ? What are bus errors, memory faults, and core dumps ?
    
    
35. When should a type cast be used ?
    
    
36. What is the difference between a string copy (strcpy) and a memory copy (memcpy)? When should each be used?
    
    
37. How can I convert a string to a number ?
    
    
38. How can I convert a number to a string ?
    
    
39. Is it possible to execute code even after the program exits the main() function?
    
    
40. What is the stack ?
    
    
41. How do you print an address ?
    
    
42. Can a file other than a .h file be included with #include ?
    
    
43. What is Preprocessor ?
    
    
44. How can you restore a redirected standard stream ?
    
    
45. What is the purpose of realloc( ) ?
    
    
46. What is the heap ?
    
    
47. How do you use a pointer to a function ?
    
    
48. What is the purpose of main( ) function ?
    
    
49. Why n++ executes faster than n+1 ?
    
    
50. What will the preprocessor do for a program ?
    
    
51. What is the benefit of using const for declaring constants ?
    
    
52. What is the easiest sorting method to use ?
    
    
53. Is it better to use a macro or a function ?
    
    
54. What are the standard predefined macros ?