linux 互斥锁应用实例.docxVIP

/*这是一个使用互斥锁实现两个线程之间同步实例，一个线程负责从标准输入设备中读取数据，而另一个线程则负责将读入的数据输出到标准输出设备上*/#include stdio.h#include unistd.h#include stdlib.h#include pthread.h#include semaphore.h#include string.hvoid *thread_function(void *arg);pthread_mutex_t work_mutex; //全局互斥锁对象，首先应该定义一个这样的互斥锁#define WORK_SIZE 1024????? //全局共享数据去char work_area[WORK_SIZE];int time_to_exit = 0;int main(int argc,char *argv[]){??? int res;??? pthread_t a_thread;??? void *thread_result;??? res = pthread_mutex_init(work_mutex, NULL); //init mutex 初始化互斥锁??? if (res != 0)??? {??????? perror(Mutex initialization failed);??????? exit(EXIT_FAILURE);??? }??? res = pthread_create(a_thread, NULL, thread_function, NULL);//create new thread创建新线程??? if (res != 0)??? {??????? perror(Thread creation failed);??????? exit(EXIT_FAILURE);??? }??? pthread_mutex_lock(work_mutex);??? ??? ??? //lock the mutex 互斥锁上锁??? printf(Input some text. Enter end to finish\n);??? while(!time_to_exit) //标志??? {??????? fgets(work_area, WORK_SIZE, stdin);??? ??? //get a string from stdin读取一行信息??????? pthread_mutex_unlock(work_mutex);??? ??? //unlock the mutex解锁??????? while(1)??? ??? {???????????????? pthread_mutex_lock(work_mutex);??? //lock the mutex??????????????????? if (work_area[0] != \0)?????????? //检查读入的内容输出没有??? ??? ?????? {?????????????????????????? pthread_mutex_unlock(work_mutex);??? //unlock the mutex如果没有输出，解锁?????????????????????????? sleep(1);?????????????????????? }??????????????????? else??? ??? ??? {??????????????????? break;??????????????????????? }??????????????? }???????? }??? pthread_mutex_unlock(work_mutex);//解锁??? printf(\nWaiting for thread to finish...\n);??? res = pthread_join(a_thread, thread_result);//等待另一个线程结束??? if (res != 0)??? {??????? perror(Thread join failed);??????? exit(EXIT_FAILURE);??? }??? printf(Thread joined\n);??? pthread_mutex_destroy(work_mutex);//销毁互斥锁??? exit(EXIT_SUCCESS);}void *thread_function(void *arg){??? sleep(1);??? pthread_mutex_lock(