麻烦看一下，多线程读者写者优先问题！（小弟新学）
麻烦看一下为什么没有输出结果的，在LINUX虚拟机上面运行的！

#include<stdio.h>

#include<pthread.h>

#include<stdlib.h>

#define MAX 5

pthread_mutex_t rmutex;

pthread_mutex_t wmutex;

pthread_mutex_t read_db;

pthread_mutex_t write_db;



int rc=0;

int wc=0;



void read_data_base()

{

printf("reading,");

sleep(3);

}

void write_data_base()

{

printf("writing");

sleep(2);

}

void *reader(void *ptr)

{

int i;

for(i=0;i<MAX;i++)

{

pthread_mutex_lock (&rmutex);

rc=rc+1;

if(rc==1){

pthread_mutex_lock(&read_db);

}

pthread_mutex_unlock(&rmutex);

read_data_base();

pthread_mutex_lock(&rmutex);

rc=rc-1;

if(rc==0){

pthread_mutex_unlock(&read_db);

}

pthread_mutex_unlock(&rmutex);

}

pthread_exit(0);

}



void *writer(void *ptr)

{

int i;

for(i=0;i<MAX;i++)

{

pthread_mutex_lock(&wmutex);

wc=wc+1;

if(wc==1)

{

pthread_mutex_lock(&read_db);

}

pthread_mutex_unlock(&wmutex);

pthread_mutex_lock(&write_db);

write_data_base();



pthread_mutex_lock(&wmutex);

wc=wc-1;

if(wc==0)

{

pthread_mutex_unlock(&read_db);

}

pthread_mutex_lock(&write_db);

pthread_mutex_unlock(&wmutex);

}

pthread_exit(0);

}



int main()

{

pthread_mutex_init(&rmutex,0);

pthread_mutex_init(&wmutex,0);

pthread_mutex_init(&read_db,0);

pthread_mutex_init(&write_db,0);



pthread_t tid1,tid2;

pthread_create(&tid1,NULL,reader,NULL);

pthread_create(&tid2,NULL,writer,NULL);

pthread_join(tid1,0);

pthread_join(tid2,0);

pthread_mutex_destroy(&rmutex);

pthread_mutex_destroy(&wmutex);

pthread_mutex_destroy(&read_db);

pthread_mutex_destroy(&write_db);



pthread_exit((void*)pthread_self());



}

------解决方案--------------------
直接一个读写锁就好了！没必要各自一个锁！太浪费！