我开始了与线程和我有一些问题解决的:Pthread的Ç同步化
这个程序会产生数的有序序列和第二个任务读取它们并将它们打印在屏幕上。如何根据需要修复此问题?
预期输出:
Consumed item: 1
Consumed item: 2
Consumed item: 3
Consumed item: 4
Consumed item: 5
Consumed item: 6
实际输出:
Consumed item: 1
Consumed item: 4
Consumed item: 7
Consumed item: 10
Consumed item: 11
Consumed item: 14
程序:
#include <stdio.h>
#include <pthread.h>
#include <time.h>
#define NBUFFERS 2
int item, in=0, out=0;
int buffer[NBUFFERS];
int stop =0;
void *ProducerTask(void *data) //This is the producer task
{
int nextp = 0;
struct timespec mytime;
mytime.tv_sec = 0;
mytime.tv_nsec = 200000000;
while (!stop) {
nanosleep(&mytime, NULL);
nextp++;
buffer[in] = nextp; /* produce a new item */
in = (in + 1) % NBUFFERS;
}
pthread_exit(0);
}
void *ConsumerTask(void *data)
{
int nextc;
struct timespec mytime;
mytime.tv_sec = 0;
mytime.tv_nsec = 500000000;
while (!stop) {
nanosleep(&mytime, NULL);
nextc = buffer[out]; /* consume a item */
out = (out + 1) % NBUFFERS;
printf("Consumed item: %d\n", nextc);
}
pthread_exit(0);
}
void *MonitorTask (void *data) //This is the monitor task
{
getchar();
stop = 1;
pthread_exit(0);
}
void main(void)
{
pthread_t task1;
pthread_t task2;
pthread_t task3;
pthread_create (&task1, NULL, ProducerTask, NULL);
pthread_create (&task2, NULL, ConsumerTask, NULL);
pthread_create (&task3, NULL, MonitorTask, NULL);
pthread_join(task1,NULL);
pthread_join(task2,NULL);
pthread_join(task3,NULL);
printf("Main program exiting.\n");
}
“修复此程序”绝对不是描述问题的好方法。您需要正确指出并描述您的问题以获得良好回应 – 2012-04-19 06:40:31
预期结果(或输出)是什么以及实际结果如何?换句话说,你的问题是什么? – 2012-04-19 06:41:25
当然!它改变了! – dani 2012-04-19 06:41:36