多线程（2）

pthread_mutex_init
函数作用：初始化互斥锁
函数原型：init pthreaad_mutex_init(pthread_mutex_t *restrict mutex,const pthread_mutex *attr_t)
函数参数：mutex：互斥锁
attr_t：快速互斥锁
返回值：成功为0，失败<0

pthread_mutex_lock
函数作用：对互斥锁上锁
函数原型：init pthreaad_mutex_lock(pthread_mutex_t *mutex）
函数参数：mutex：互斥锁
返回值：成功为0，失败<0

//判断是否上锁init pthreaad_mutex_trylock(pthread_mutex_t *mutex);//解锁init pthreaad_mutex_unlock(pthread_mutex_t *mutex);//销毁锁init pthreaad_mutex_destroy(pthread_mutex_t *muteex);

程序

#include <stdio.h>#include <stdlib.h>#include <pthread.h>#define  THREAD_NUM  3#define  REPEAT_NUM  3#define  DELAY_TIME_LEVELS  6.0  pthread_mutex_t mutex;void *thrd_func(void *arg){    int thrd_num = (int)arg;    int delay_time =0, count=0;    int res;    res = pthread_mutex_lock(&mutex);    printf("Thread %d is starting\n", thrd_num);    for(count=0; count<REPEAT_NUM; count++)    {        printf("\tThread %d:job %d delay=%d\n", thrd_num,count);    }    printf("Thread %d finish\n", thrd_num);    pthread_mutex_unlock(&mutex);    pthread_exit(NULL);}int main(void){   pthread_t thread[THREAD_NUM];   int no=0, res;   void *thrd_ret;   pthread_mutex_init(&mutex, NULL);   for(no=0; no<THREAD_NUM; no++)   {       res=pthread_create(&thread[no], NULL, thrd_func, (void *)no);   }   printf("creatr threads success\nwaiting for threads to finish....\n");   for(no=0; no<THREAD_NUM; no++)   {      res=pthread_join(thread[no], &thrd_ret);   }thread_mutex_destroy(&mutex);   return 0;}