#include
#include

#define?W_NUM?5????//最大寫者數
#define?R_NUM?10??//最大讀者數
#define?MAX_NUM?10

	
pthread_mutex_t?write_lock;??????
pthread_mutex_t?read_lock;????
pthread_mutex_t?change_writer_num_lock;???
pthread_mutex_t?chane_reader_num_lock;???

pthread_t?writers[MAX_NUM];
pthread_t?readers[MAX_NUM];

int?writer_cnt?=?0;
int?reader_cnt?=?0;


void?*writer（void?*writer_id）{
	int?*ptr_idtask_id;
	ptr_id?=?（int?*）writer_id;
	task_id?=?*ptr_id;

	printf（“	Writer?%d?send?write?require\n“task_id）;

	
	pthread_mutex_lock（&change_writer_num_lock）;
	writer_cnt++;
	//printf（“??%d\n“writer_cnt）;
	if（writer_cnt?==?1）{
		pthread_mutex_lock（&read_lock）;?????//???讀者將阻塞在這兒
	}
	pthread_mutex_unlock（&change_writer_num_lock）;

	pthread_mutex_lock（&write_lock）;
	printf（“	Writer?%d?begin?to?writing\n“task_id）;
	printf（“	Writer?%d?is?writing.......\n“task_id）;
	sleep（1）;
	printf（“	Writer?%d?finished?writing\n“task_id）;
	//sleep（2）;
	pthread_mutex_unlock（&write_lock）;

	pthread_mutex_lock（&change_writer_num_lock）;
	writer_cnt--;
	//printf（“??%d\n“writer_cnt）;
	if（writer_cnt?==?0）{
		pthread_mutex_unlock（&read_lock）;
	}
	pthread_mutex_unlock（&change_writer_num_lock）;
	sleep（3）;??
	
	pthread_exit（NULL）;
}

void?*reader（void?*reader_id）{
	int?*ptr_idtask_id;
	ptr_id?=?（int?*）reader_id;
	task_id?=?*ptr_id;

	printf（“Reader?%d?send?read?require\n“task_id）;
	
	pthread_mutex_lock（&read_lock）;????//readers?choked?here
	pthread_mutex_lock（&chane_reader_num_lock）;
	reader_cnt++;
	if（reader_cnt?==?1）{
		pthread_mutex_lock（&write_lock）;
	}
	pthread_mutex_unlock（&chane_reader_num_lock）;
	pthread_mutex_unlock（&read_lock）;

	printf（“Reader?%d?begin?to?reading\n“task_id）;
	printf（“Reader?%d?is?reading.......\n“task_id）;
	sleep（1）;
	printf（“Reader?%d?finished?reading\n“task_id）;
	//sleep（1）;

	pthread_mutex_lock（&chane_reader_num_lock）;
	reader_cnt--;
	if（reader_cnt?==?0）{
		pthread_mutex_unlock（&write_lock）;
	}
	pthread_mutex_unlock（&chane_reader_num_lock）;
	sleep（3）;
	
	pthread_exit（NULL）;
}

int?main（）{
	
	int?writer_id[MAX_NUM];
	int?reader_id[MAX_NUM];

	pthread_mutex_init（&write_lockNULL）;
	pthread_mutex_init（&read_lockNULL）;
	pthread_mutex_init（&change_writer_num_lockNULL）;
	pthread_mutex_init（&chane_reader_num_lockNULL）;

	int?i_W?=?0;
	int?i_R?=?0;
	
	for（i_W?=?0;?i_W?		writer_id[i_W]?=?i_W;
		pthread_create（&writers[i_W]NULLwriter（void?*）&writer_id[i_W]）;
		//sleep（0.5）;
	}
	for（i_R?=?0;?i_R?		reader_id[i_R]?=?i_R;
		pthread_create（&readers[i_R]NULLreader（void?*）&reader_id[i_R]）;
		//sleep（0.5）;
	}

????sleep（10）;

????for（i_W?=?0;?i_W?????	pthread_join（writers[i_W]NULL）;
????}
????for（i_R?=?0;?i_R?????	pthread_join（readers[i_R]NULL）;
????}

	return?0;

}

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2014-04-18?10:39??writer_reader\
?????文件????????2820??2014-04-18?10:37??writer_reader\main.c