1. #include <pthread.h>
2. #include <stdio.h>
3. #include <unistd.h>
4. #include <time.h>
5. #include <stdlib.h>
6.  
7. #define NUMBER_OF_PHILOSOPHERS 5
8.  
9. void *philosopher(void *);
10. void think(int);
11. void pickUp(int);
12. void eat(int);
13. void putDown(int);
14.  
15. pthread_mutex_t chopsticks[NUMBER_OF_PHILOSOPHERS];
16. pthread_t philosophers[NUMBER_OF_PHILOSOPHERS];
17. pthread_attr_t attributes[NUMBER_OF_PHILOSOPHERS];
18.  
19. int main() {
20.         int i;
21.         srand(time(NULL));
22.         for (i = 0; i < NUMBER_OF_PHILOSOPHERS; ++i) {
23.                 pthread_mutex_init(&chopsticks[i], NULL);
24.         }
25.  
26.         for (i = 0; i < NUMBER_OF_PHILOSOPHERS; ++i) {
27.                 pthread_attr_init(&attributes[i]);
28.         }
29.        
30.         for (i = 0; i < NUMBER_OF_PHILOSOPHERS; ++i) {
31.                 pthread_create(&philosophers[i], &attributes[i], philosopher, (void *)(i));
32.         }
33.  
34.         for (i = 0; i < NUMBER_OF_PHILOSOPHERS; ++i) {
35.                 pthread_join(philosophers[i], NULL);
36.         }
37.         return 0;
38. }
39.  
40. void *philosopher(void *philosopherNumber) {
41.         while (1) {
42.                 think(philosopherNumber);
43.                 pickUp(philosopherNumber);
44.                 eat(philosopherNumber);
45.                 putDown(philosopherNumber);
46.         }
47. }
48.  
49. void think(int philosopherNumber) {
50.         int sleepTime = rand() % 3 + 1;
51.         printf("Philosopher %d will think for %d secondsn", philosopherNumber, sleepTime);
52.         sleep(1);
53. }
54.  
55. void pickUp(int philosopherNumber) {
56.        
57.                 int right = (philosopherNumber + 1) % NUMBER_OF_PHILOSOPHERS;
58.         int left = (philosopherNumber + NUMBER_OF_PHILOSOPHERS) % NUMBER_OF_PHILOSOPHERS;
59.        
60.                 printf("Philosopher %d is waiting to pick up chopstick %dn", philosopherNumber, left);
61.                 pthread_mutex_lock(&chopsticks[left]);
62.                 printf("Philosopher %d picked up chopstick %dn", philosopherNumber, left);
63.                
64. printf("Philosopher %d is waiting to pick up chopstick %dn", philosopherNumber, right);
65.                 pthread_mutex_lock(&chopsticks[right]);
66.                 printf("Philosopher %d picked up chopstick %dn", philosopherNumber, right);
67.        
68. }
69.  
70. void eat(int philosopherNumber) {
71.         int eatTime = rand() % 3 + 1;
72.         printf("Philosopher %d will eat for %d secondsn", philosopherNumber, eatTime);
73.         sleep(eatTime);
74. }
75.  
76. void putDown(int philosopherNumber) {
77.         printf("Philosopher %d will will put down her chopsticksn", philosopherNumber);
78.         pthread_mutex_unlock(&chopsticks[(philosopherNumber + 1) % NUMBER_OF_PHILOSOPHERS]);
79.         pthread_mutex_unlock(&chopsticks[(philosopherNumber + NUMBER_OF_PHILOSOPHERS) % NUMBER_OF_PHILOSOPHERS]);
80. }