58 lines
1.2 KiB
C
58 lines
1.2 KiB
C
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#include <stdio.h>
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#include <pthread.h>
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#include <stdlib.h>
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#include <semaphore.h>
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//设置办理业务的人数
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int num = 5;
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//创建信号量
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sem_t sem;
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//模拟办理业务的过程
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void *get_service(void *arg)
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{
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int id = *((int *)arg);
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//信号量成功“减 1”后才能继续执行
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if (sem_wait(&sem) == 0)
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{
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printf("---customer%d 正在办理业务\n", id);
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sleep(2);
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printf("---customer%d 已办完业务\n", id);
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//信号量“加 1”
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sem_post(&sem);
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}
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return 0;
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}
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int main()
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{
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int flag, i, j;
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//创建 5 个线程代表 5 个人
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pthread_t customer[5];
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//初始化信号量
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sem_init(&sem, 0, 2);
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for (i = 0; i < num; i++)
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{
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flag = pthread_create(&customer[i], NULL, get_service, &i);
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if (flag != 0)
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{
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printf("线程创建失败!\n");
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return 0;
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}
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else
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{
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printf("customer%d 来办理业务\n", i);
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}
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sleep(1);
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}
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for (j = 0; j < num; j++)
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{
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flag = pthread_join(customer[j], NULL);
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if (flag != 0)
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{
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printf("tid=%d 等待失败！", customer[i]);
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return 0;
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}
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}
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sem_destroy(&sem);
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return 0;
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}
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