在本机器上能通过的代码，放在网路上有关文件操作的代码出现下面的错误信息，
是不是我在主机没有写权限？请指教！
Warning: fopen(./data/main.dat): failed to open stream: Permission denied in /webroot/www.yide-bio.com/www/info-dajiashuo.php on line 530
Warning: fwrite(): supplied argument is not a valid stream resource in /webroot/www.yide-bio.com/www/info-dajiashuo.php on line 532
Warning: fclose(): supplied argument is not a valid stream resource in /webroot/www.yide-bio.com/www/info-dajiashuo.php on line 533
