生产者与消费者问题 Linux and c，有bug谁能帮忙看一下
错误：in file included from /user/include/sys/shm.h:31
from pac.c:33
/user/included/bits/shm.h:40:two or more data types in declaration of '_getpagesize'
这是源码：
#include<errno.h>
#include<stdlib.h>
#include<stdio.h>
#include<unistd.h>
...