Top 50 C language interview questions | Frequently asked C language interview questions

INTERVIEW QUESTIONS

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 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 aarray ?
31.    What is the benefit of using #definto declare a constant
32.    How can search for data in a linked list ?
33.    Why shld 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 ?