php程序运行出现错误，不懂哪出问题了

Warning: fopen(./cfg_qq_file.txt) [function.fopen]: failed to open stream: Permission denied in
Warning: fclose(): supplied argument is not a valid stream resource in
我给文件夹都有写入权限，也用ftp把整个网站文件夹和文件权限都改成777了，还是一样。不懂哪有问题。