请问这个是什么意思，开启什么作用？

在VSFTPD.CONF看到的

# You may activate the "-R" option to the builtin ls. This is disabled by
# default to avoid remote users being able to cause excessive I/O on large
# sites. However, some broken FTP clients such as "ncftp" and "mirror" assume
# the presence of the "-R" option, so there is a strong case for enabling it.
#ls_recurse_enable=YES　　　　　　

防止递归下载？
如下载一整个文件夹　　　　　　

明白，谢谢