1 #include <pthread.h>
2
3 int pthread_barrier_init(pthread_barrier_t *restrict barrier, const pthread_barrierattr_t *restrict attr, unsigned count);

1 #include <pthread.h>
2
3 int pthread_barrier_wait(pthread_barrier_t *barrier);

1 #include <pthread.h>
2
3 int pthread_barrier_destroy(pthread_barrier_t *barrier);

 1 /**
 2  * @file pthread_barrier.c
 3  */
 4
 5 #include <stdio.h>
 6 #include <stdlib.h>
 7 #include <string.h>
 8 #include <unistd.h>
 9 #include <pthread.h>
10
11 /* 屏障总数 */
12 #define PTHREAD_BARRIER_SIZE 4
13
14 /* 定义屏障 */
15 pthread_barrier_t barrier;
16
17 void err_exit(const char *err_msg)
18 {
19     printf("error:%s\n", err_msg);
20     exit(1);
21 }
22
23 void *thread_fun(void *arg)
24 {
25     int result;
26     char *thr_name = (char *)arg;
27
28     /* something work */
29
30     printf("线程%s工作完成...\n", thr_name);
31
32     /* 等待屏障 */
33     result = pthread_barrier_wait(&barrier);
34     if (result == PTHREAD_BARRIER_SERIAL_THREAD)
35         printf("线程%s，wait后第一个返回\n", thr_name);
36     else if (result == 0)
37         printf("线程%s，wait后返回为0\n", thr_name);
38
39     return NULL;
40 }
41
42 int main(void)
43 {
44     pthread_t tid_1, tid_2, tid_3;
45
46     /* 初始化屏障 */
47     pthread_barrier_init(&barrier, NULL, PTHREAD_BARRIER_SIZE);
48
49     if (pthread_create(&tid_1, NULL, thread_fun, "1") != 0)
50         err_exit("create thread 1");
51
52     if (pthread_create(&tid_2, NULL, thread_fun, "2") != 0)
53         err_exit("create thread 2");
54
55     if (pthread_create(&tid_3, NULL, thread_fun, "3") != 0)
56         err_exit("create thread 3");
57
58     /* 主线程等待工作完成 */
59     pthread_barrier_wait(&barrier);
60     printf("所有线程工作已完成...\n");
61
62     sleep(1);
63     return 0;
64 }