The document discusses implementing the strtok() string tokenization function. It explains that strtok() breaks a string into tokens based on delimiters. The document then provides pseudocode to implement a custom strtok() function by iterating through the string, overwriting delimiter characters with null terminators to create tokens, and returning a pointer to each token. Sample input/output is provided. The objective is stated as understanding string functions, with prerequisites of strings, storage classes, and pointers.

1. Team Emertxe
Strings and Storage
Classes

2. Assignment 7

3. Assignment 7

4. Assignment 7
WAP to implement strtok function

5. Assignment 7
WAP to implement strtok function
Input:

6. Assignment 7
WAP to implement strtok function
Input: Read two Strings.

7. Assignment 7
WAP to implement strtok function
Input: Read two Strings.
Output:

8. Assignment 7
WAP to implement strtok function
Input: Read two Strings.
Output: Print tokens from string.

9. Assignment 7
What is strtok() function?

10. Assignment 7
What is strtok() function?
 The strtok() function breaks a string into a sequence of zero or
more nonempty tokens.
 On the first call to strtok(), the string to be parsed should be
specified in str. In each subsequent call that should parse the
same string, str must be NULL.

11. Assignment 7
What is strtok() function?
 The strtok() function breaks a string into a sequence of zero or
more nonempty tokens.
 On the first call to strtok(), the string to be parsed should be
specified in str. In each subsequent call that should parse the
same string, str must be NULL.
Prototype: char *strtok(char *str, const char *delim);

12. Assignment 7
Let’s understand how strtok() works:

13. Assignment 7
Let’s understand how strtok() works:

14. Assignment 7
Let’s understand how strtok() works:
What will be printed?

15. Assignment 7
Let’s understand how strtok() works:
“Are” will be printed
O/p of the program:
Are

16. Assignment 7
Let’s understand how strtok() works:
What will be printed?

17. Assignment 7
Let’s understand how strtok() works:
“Are” will be printed
“Are” will be printed
O/p of the program:
Are
Are

18. Assignment 7
Let’s understand how strtok() works:
But, the next token
should be printed is
“you”
“Are” will be printed
“Are” will be printed
O/p of the program:
Are
Are

19. Assignment 7
Let’s understand how strtok() works:
What will be printed?
What will be printed?

20. Assignment 7
Let’s understand how strtok() works:
“you” will be printed
“Are” will be printed
O/p of the program:
Are
you

21. Assignment 7
Let’s understand how strtok() works:
O/p of the program:
Are
you
How will you print the
remaining tokens?

22. Assignment 7
Let’s understand how strtok() works:
What is the output?

23. Assignment 7
Let’s understand how strtok() works:
O/p of the program:
Are
You
okay

24. Assignment 7
How to implement your own strtok() function?

25. Assignment 7
How to implement your own strtok() function?
 Input: str = “Are;you:okay”
delim = “;:”
A r e ; y o u : o k a y 0
; : 0
str
delim String containing delimiters,
these delimiters has to be
matched with each and every
character of str

26. Assignment 7
A r e ; y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos

27. Assignment 7
A r e ; y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos

28. Assignment 7
A r e ; y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos

29. Assignment 7
A r e ; y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos

30. Assignment 7
A r e ; y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos

31. Assignment 7
A r e ; y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos

32. Assignment 7
A r e ; y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos Here at pos 3, delimiter is
encountered, so overwrite that
byte with ‘0’

33. Assignment 7
A r e 0 y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos Return the address using str +
start_index and do pos++

34. Assignment 7
A r e 0 y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos Return the address using str +
start_index and do pos++
Output:
Are

35. Assignment 7
A r e 0 y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are

36. Assignment 7
A r e 0 y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are

37. Assignment 7
A r e 0 y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are

38. Assignment 7
A r e 0 y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are

39. Assignment 7
A r e 0 y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are

40. Assignment 7
A r e 0 y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are

41. Assignment 7
A r e 0 y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are

42. Assignment 7
A r e 0 y o u : o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are
Here at pos 7, delimiter is
encountered, so overwrite that
byte with ‘0’

43. Assignment 7
A r e 0 y o u 0 o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are
You
Return the address using str +
start_index and do pos++

44. Assignment 7
A r e 0 y o u 0 o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are
You

45. Assignment 7
A r e 0 y o u 0 o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are
You

46. Assignment 7
A r e 0 y o u 0 o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are
You

47. Assignment 7
A r e 0 y o u 0 o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are
You

48. Assignment 7
A r e 0 y o u 0 o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are
You

49. Assignment 7
A r e 0 y o u 0 o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are
You

50. Assignment 7
A r e 0 y o u 0 o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are
You

51. Assignment 7
A r e 0 y o u 0 o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are
You

52. Assignment 7
A r e 0 y o u 0 o k a y 0
; : 0
str
delim
0 1 2 3 4 5 6 7 8 9 10 11 12
start_index
 Input: str = “Are;you:okay”
delim = “;:”
pos
Output:
Are
You
okay
Return the address using str +
start_index

53. Assignment 7
Sample execution:-

54. Assignment 7
Sample execution:-

55. Assignment 7
Sample execution:-

56. Assignment 7
Pre-requisites:-

57. Assignment 7
Pre-requisites:-
⮚Strings

58. Assignment 7
Pre-requisites:-
⮚Strings
⮚Storage Classes

59. Assignment 7
Pre-requisites:-
⮚Strings
⮚Storage Classes
⮚Pointers

60. Assignment 7
Pre-requisites:-
⮚Strings
⮚Storage Classes
⮚Pointers
Objective:-

61. Assignment 7
Pre-requisites:-
⮚Strings
⮚Storage Classes
⮚Pointers
Objective:-
To understand the concept of String functions.

62. Team Emertxe
Thank you