读写锁实现读写者问题

注意：LINUX 读写锁是写者优先

/*producer and constmer*/
#include
#include
#include
#include
pthread_rwlock_t rwlock;
int good = 0;
void *writer(void *argv)
{
	while(1)
	{
		pthread_rwlock_wrlock(&rwlock);
		good = rand() % 1000;
		printf("%u witre:%d\n",(unsigned int)pthread_self() % 100,good);
		pthread_rwlock_unlock(&rwlock);
		sleep(rand()%2);
	}
	return NULL;
}
void *reader(void *argv)
{
	while(1)
	{
		pthread_rwlock_rdlock(&rwlock);
		printf("%u read:%d\n",(unsigned int)pthread_self() % 100,good);
		pthread_rwlock_unlock(&rwlock);
		sleep(rand()%2);

	}
	return NULL;
}
void main()
{
	pthread_t pt[8];
	int i;
	pthread_rwlock_init(&rwlock,NULL);
	for(i=0;i < 3;i++)
	{
		pthread_create(&pt[i],NULL,writer,NULL);
	}
	for(;i<8;i++)
		pthread_create(&pt[i],NULL,reader,NULL);
	for(i=0;i<8;i++)
		pthread_join(pt[i],NULL);
	pthread_rwlock_destroy(&rwlock);
}