1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
#include <pthread.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <time.h>
#include <math.h>
int x;
pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t cond;
void*
t1_fn(void* arg)
{
int m;
while (1) {
usleep(100 * 1000);
m = rand() % 11;
pthread_mutex_lock(&mutex);
printf("th1: (x=%d, m=%d):", x, m);
if (x == -1) {
break;
} else if (x == m) {
printf("RISPOSTA CORRETTA\n");
x = -1;
break;
} else if (abs(x-m) > 5) {
printf("risposta MOLTO sbagliata\n");
pthread_mutex_unlock(&mutex);
pthread_cond_wait(&cond, &mutex);
} else {
printf("risposta sbagliata\n");
}
pthread_mutex_unlock(&mutex);
}
pthread_mutex_unlock(&mutex);
pthread_exit(NULL);
}
void*
t2_fn(void* arg)
{
while (1) {
usleep(300* 1000);
pthread_mutex_lock(&mutex);
printf("\tthread 2 %d\n", x);
if (x == -1) {
pthread_mutex_unlock(&mutex);
pthread_exit(NULL);
}
pthread_cond_signal(&cond);
pthread_mutex_unlock(&mutex);
}
}
int
main()
{
pthread_t t1, t2;
srand(time(NULL));
x = rand() % 11;
pthread_create(&t1, NULL, t1_fn, NULL);
pthread_create(&t2, NULL, t2_fn, NULL);
pthread_join(t1, NULL);
pthread_join(t2, NULL);
return 0;
}
|
