1 #include <stdio.h>
2 #include <pthread.h>
3 #include <semaphore.h>
4
5 #define UPBOUND 100
6
7 sem_t sem1;
8 sem_t sem2;
9
10 //int i=0;
11
12 void *threadfunc1(void *p)
13 {
14 int i=0;
15 while(i<100)
16 {
17 sem_wait(&sem1);
18 i++;
19 printf("111 thread i is %d\n",i);
20 sem_post(&sem2);
21 }
22 return NULL;
23 }
24
25
26 void *threadfunc2(void *p)
27 {
28 int i=0;
29 while(i<100)
30 {
31 sem_wait(&sem2);
32 i++;
33 printf("222 thread i is %d\n",i);
34 sem_post(&sem1);
35 }
36 return NULL;
37 }
38
39 int main()
40 {
41 sem_init(&sem1, 0, 1); //线程间共享，初值为1
42 sem_init(&sem2, 0, 0);
43
44 pthread_t tid1=0, tid2=0;
45
46 pthread_create(&tid1,NULL,&threadfunc1,NULL);
47 pthread_create(&tid2,NULL,&threadfunc2,NULL);
48
49 pthread_join(tid1,NULL);
50 pthread_join(tid2,NULL);
51
52 sem_destroy(&sem1);
53 sem_destroy(&sem2);
54
55 return 0;
56 }
