#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#define THREAD_NUMBER 3
#define REPEAT_NUMBER 3
#define DELAY_TIME_LEVELS 10.0
pthread_mutex_t mutex;
void *thrd_func(void *arg)
{
int thrd_num=(int)arg;
int delay_time=0,count=0;
int res;
/*互斥锁上锁*/
res=pthread_mutex_lock(&mutex);
if(res)
{
printf("Thread %d lock failed\n",thrd_num);
pthread_exit(NULL);
}
printf("Thread %d is starting\n",thrd_num);
for(count=0;count<REPEAT_NUMBER;count++)
{
delay_time=(int)(rand()*DELAY_TIME_LEVELS/(RAND_MAX))+1;
sleep(delay_time);
printf("\tThread %d :job %d delay=%d\n",thrd_num,count,delay_time);
}
printf("Thread %d finished\n",thrd_num);
pthread_mutex_unlock(&mutex);
pthread_exit(NULL);
}
int main(void)
{
pthread_t thread[THREAD_NUMBER];
int no=0,res;
void *thrd_ret;
srand(time(NULL));
/*互斥锁初始化*/
pthread_mutex_init(&mutex,NULL);
for(no=0;no<THREAD_NUMBER;no++)
{
res=pthread_create(&thread[no],NULL,thrd_func,(void*)no);
if(res!=0)
{
printf("Create thread %d failed\n",no);
exit(res);
}
}
printf("Create treads success\n Waiting for threads to finished...\n");
for(no=0;no<THREAD_NUMBER;no++)
{
res=pthread_join(thread[no],&thrd_ret);
if(!res)
{
printf("Thread %d joined\n",no);
}
else
{
printf("Thread %d join failed\n",no);
}
/*互斥锁解锁*/
//pthread_mutex_unlock(&mutex);//解锁位置
}
pthread_mutex_destroy(&mutex);
return 0;
}
输出结果为：
程序目的是创建3个线程，每个线程随机延时，但按照程序运行顺序不应该是按0.1.2顺序输出吗？为什么会是2.1.0输出顺序？
本人刚开始学linux系统编程，求各位大神不吝赐教。
