1. Function: Declaration
<return type> <identifier>( <parameter>, ... );

2. Function: Declaration
unsigned int square( int number );
Declaration creates prototype (older versions of C didn't require parameter list, no prototype created)

3. Function: Declaration
unsigned int square( int );

4. Function: Declaration
unsigned int square( int number );

5. Function: Definition
<return type> <identifier>( <parameter>, ... ) {
<statements> }

6. Function: Definition unsigned int square( int number ) {
return number * number; }
Definition “acts” as declaration if no declaration exists
Definition must match prototype if declaration exists

7. Function: Calling unsigned int two_squared = square( 2 );
All arguments passed by value i.e. copy made
Open source 07 (functions and overloading)
Explain _Generic (compile time macro)

8. Exercises Open exercises/ex06/main.c
Declare a new function with the following prototype:
unsigned int gcd( unsigned int a, unsigned int b )
Define the function so that it implements Euclid's
greatest common divisor algorithm as follows:
if b equals 0, return a
else return gcd( b, a modulo b ) ←- Recursive call to gcd()
Build using Makefile
Run & test. Output to console should be “GCD = 8”.

9. Enumeration enum [<identifier>] {
<enumeration constant> [= <constant expression>], .
<enumeration constant> [= <constant expression>] };

10. Enumeration enum MultipleChoice { OPTION_A, OPTION_B, OPTION_C,
OPTION_D,
ALL_OF_THE_ABOVE };

11. Enumeration enum MultipleChoice { OPTION_A, // 0 OPTION_B, // 1
OPTION_C, // 2
OPTION_D, // 3
ALL_OF_THE_ABOVE // 4 };

12. Enumeration enum MultipleChoice { OPTION_A = 10, OPTION_B, OPTION_C,
OPTION_D,
ALL_OF_THE_ABOVE };

13. Enumeration enum MultipleChoice { OPTION_A = 10, // 10 OPTION_B, // 11
OPTION_C, // 12
OPTION_D, // 13
ALL_OF_THE_ABOVE // 14 };

14. Enumeration enum MultipleChoice { OPTION_A, // 0 OPTION_B, // 1
OPTION_C = 12, // 12
OPTION_D, // 13
ALL_OF_THE_ABOVE // 14 };

15. Enumeration
enum MultipleChoice question1 = OPTION_C;

16. Structures struct [<identifier>] { <struct declarator>; .};

17. Structures struct RGBA { float red; float green; float blue;
float alpha; };

18. Structures struct RGBA polygon_colour; polygon_colour.red = 0.5f;
polygon_colour.green = 0.5f;
polygon_colour.blue = 0.5f;
polygon_colour.alpha = 1.0f;

19. Typedef
typedef struct RGBA RGBA;

20. Typedef
typedef struct RGBA RGBA;

21. Typedef
typedef struct RGBA RGBA;

22. Typedef typedef struct RGBA RGBA; Open source 08
Add typedef for enum and struct
Briefly explain char * as string
VLA char[] cannot be used, except at the end of the struct

23. Exercises Open exercises/ex07/main.c
Define a new enum called Genre, with two or three constants
for movie genres
Define a new struct called BluRay, with the following
attributes:
char *title
char *director
unsigned short year
enum Genre genre
Define a new function that creates and returns a new BluRay,
and another that prints a BluRay to console
Create a BluRay in main(), and print to console, using the new
functions
Build using Makefile
Run & test

24. Pointers
char some_char = 'c';
char *char_ptr = &some_char;

25. Pointers
char some_char = 'c';
char *char_ptr = &some_char;

26. char *char_ptr = &some_char;
Pointers
char some_char = 'c';
char *char_ptr = &some_char;
base-type specifier

27. char *char_ptr = &some_char;
Pointers
char some_char = 'c';
char *char_ptr = &some_char;
declarator

28. char *char_ptr = &some_char;
Pointers
char some_char = 'c';
char *char_ptr = &some_char;
identifier

29. char *char_ptr = &some_char;
Pointers
char some_char = 'c';
char *char_ptr = &some_char;
derived type

30. char *char_ptr = &some_char;
Pointers
char some_char = 'c';
char *char_ptr = &some_char;
optional initialiser

31. char *char_ptr = &some_char;
Pointers
char some_char = 'c';
char *char_ptr = &some_char;
address-of operator

32. Pointers
char some_char = 'c';
char *char_ptr = 0xA1;

33. Pointers
char some_char = 'c';
char *char_ptr = &some_char;

34. char *char_ptr = (char *)0xA1;
Pointers
char *char_ptr = (char *)0xA1;
'a' 12
... 8
'c'
'Z'
...
0x00
0x01
0x02
0xA0
0xA1
0xA2

35. Pointers char some_char = 'c'; char *char_ptr = &some_char;
printf( "I am pointing to %c", *char_ptr );
Open source 09
Arrays decay to pointer
Pointer arithmetic – warn about pointing to other data
Show loop using pointer arithmetic (assign back to pointer)
Index operator
dereference operator

36. Exercises Open exercises/ex08/main.c
Complete the definition for swap(). The function must swap
the values of its two arguments.
Create two int variables in main() (initialise them to any
values)
Output the values of the variables before and after calling
swap()
Build using Makefile
Run & test

37. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;

38. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;
main()

39. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;
main()

40. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;
some_func()
main()

41. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;
some_func()
main()

42. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;
another_func()
some_func()
main()

43. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;
another_func()
some_func()
main()

44. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;
some_func()
main()

45. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;
main()

46. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;
main()

47. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;
main()

48. Stack void another_func() { ... } void some_func() { another_func();
int main() {
some_func();
return 0;
Open source 10

49. Exercises
Open exercises/ex09/main.c
Define the function zero_fill(). The function must fill mem
with zeroes for the specified size.
Define the function alloc_and_zero(). The function must
allocate memory on the heap, of the specified size, fill it
with zeroes, and return a pointer to the new heap memory
Allocate a new instance of Date using alloc_and_zero().
Output the content of year, month, day to console.
Build using Makefile
Run & test. Ensure that output is zeroes.
Open source 11
Explain function pointers before exercise on next slide

50. Exercises Open source 12 Open exercises/ex10/main.c
Create a typedef alias for the function pointer type of
the func parameter in for_each(). Rewrite the func
parameter to use your new typedef.
Define the function for_each(). The function must call func
for each value in the array, passing in the value and its
associated index.
Define the function print_idx_val(). The function must
print the value and index parameters to console e.g.
"Value 0 is 100".
In main(), call for_each() with the test values supplied
and print_idx_val()
Build using Makefile
Run & test
Open source 12

51. File Size fseek( file, 0, SEEK_END ); long file_size = ftell( file );
rewind( file );

52. Exercises Open source 12 Open exercises/ex11/main.c
Define the function read_in_file(). The function must read
in the contents of the file, at file_name, into memory and
return it. If an error occurs, return NULL.
HINT: retrieve the file size to determine the amount of
memory to allocate.
Define the function print_buffer(). The function must
output the contents of buffer to the console.
Read implementation of main(). Ensure you understand.
Build using Makefile
Run & test using haiku.txt
Open source 12

53. Libraries & #include Directive
main.c
mylib.h
#include “mylib.h”
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#include “mylib.h”
void my_func( ... ) {
... }

54. Libraries & #include Directive
main.c
mylib.h
#include “mylib.h”
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#include “mylib.h”
void my_func( ... ) {
... }
Library header file with single function declaration
Explain inclusion guard

55. Libraries & #include Directive
main.c
mylib.h
#include “mylib.h”
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#pragma once
void my_func( ... );
mylib.c
#include “mylib.h”
void my_func( ... ) {
... }
#pragma once inclusion guard

56. Libraries & #include Directive
main.c
mylib.h
#include “mylib.h”
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#include “mylib.h”
void my_func( ... ) {
... }
Library header file with single function declaration
Explain inclusion guard

57. Libraries & #include Directive
main.c
mylib.h
#include “mylib.h”
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#include “mylib.h”
void my_func( ... ) {
... }
Library source file
#include explanation to follow
Contains the definition for the function declared in header

58. Libraries & #include Directive
main.c
mylib.h
#include “mylib.h”
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#include “mylib.h”
void my_func( ... ) {
... }

59. Libraries & #include Directive
main.c
mylib.h
#include “mylib.h”
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#include “mylib.h”
void my_func( ... ) {
... }

60. Libraries & #include Directive
main.c
mylib.h
#include “mylib.h”
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#include “mylib.h”
void my_func( ... ) {
... }
Explain #include is preprocessor
Point out quotes in #include

61. Libraries & #include Directive
main.c
mylib.h
#include “mylib.h”
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#include “mylib.h”
void my_func( ... ) {
... }
Explain inclusion guard

62. Libraries & #include Directive
main.c
mylib.h
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#include “mylib.h”
void my_func( ... ) {
... }

63. Libraries & #include Directive
main.c
mylib.h
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#include “mylib.h”
void my_func( ... ) {
... }

64. Libraries & #include Directive
main.c
mylib.h
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
void my_func( ... ) {
... }

65. Libraries & #include Directive
main.c
mylib.h
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
void my_func( ... ) {
... }

66. Libraries & #include Directive
main.c
mylib.h
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
int main( int argc, char *argv[] ) {
my_func( ... );
return 0; }
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
mylib.c
#ifndef MYLIB_H
#define MYLIB_H
void my_func( ... );
#endif
void my_func( ... ) {
... }
Compilation Unit

67. Libraries & Compilation
main.c
mylib.c cc cc
main.o
mylib.o ld
binary executable

68. Libraries & Compilation
main.c
mylib.c cc cc
main.o
mylib.o ld
binary executable

69. Libraries & Compilation
main.c
mylib.c cc cc
main.o
mylib.o ld
binary executable

70. Libraries & Compilation
main.c
mylib.c cc cc
main.o
mylib.o ld
binary executable

71. Libraries & Compilation
main.c
mylib.c cc cc
main.o
mylib.o ld
binary executable

72. Libraries & Compilation
main.c
mylib.c cc cc
main.o
mylib.o ld
Not really a distributable library
See how to make a reusable static library now
binary executable

73. Libraries & Compilation
main.c cc
main.o
mylib.a ld
binary executable

74. Libraries & Compilation
main.c
Static Library cc
main.o
mylib.a ld
binary executable

75. Exercises Open source 12 Open exercises/ex12/src/mystring.c
Define the function my_streq() that is declared in
exercises/ex12/include/mystring.h. The function must
compare the two argument strings to determine if they’re
equal.
Add a new test to exercises/ex12/tests/main.c to test your
new function
Build lib and tests using Makefile
Run tests
Open source 12

76. Exercises Create the header and implementation files for a new library
called vector
Define a new struct called Vector in your header file. The
Vector struct should have the following attributes
float x; float y; float z;
Declare and define a function called vec_add(). The function
must take two Vector arguments and return a Vector containing
their sum.
Declare and define a function called vec_dot(). The function
must take two Vector arguments and return their dot product,
calculated as:
( vec1.x * vec2.x ) + ( vec1.y * vec2.y ) + ( vec1.z * vec2.z )
Create your own tests for the functions
Build using Makefile
Run tests

77. Linked Lists
head

78. Linked Lists: Append
head

79. Linked Lists: Append
head

80. Linked Lists: Append
head

81. Linked Lists: Insert
head

82. Linked Lists: Insert
head

83. Linked Lists: Insert
head

84. Linked Lists: Insert
head

85. Linked Lists: Insert
head

86. Linked Lists: Delete
head

87. Linked Lists: Delete
head

88. Linked Lists: Delete
head

89. Linked Lists: Delete
head

90. Linked Lists: Delete
head

91. Linked Lists: Delete
head

92. Linked Lists: Search
Search for 8
head 21 60 8 17 31

93. Linked Lists: Search
Search for 8
head 21 60 8 17 31

94. Linked Lists: Search
Search for 8
head 21 60 8 17 31

95. Linked Lists: Search
Search for 8
head 21 60 8 17 31

96. Linked Lists: Search
Search for 8
head 21 60 8 17 31

97. Linked Lists: Search
Search for 8
head 21 60 8 17 31

98. Linked Lists: Search
Search for 8
head 21 60 8 17 31

99. Linked Lists: Search What would happen if 8 didn’t exist? Search for 8
head 21 60 8 17 31
What would happen if 8 didn’t exist?