downlog()
{
(
echo "open ${1} ${2}";
echo "user ${3} ${4}";
echo "bell"
echo "hash";
echo "binary";
echo "get ${5} ${6}";
echo "close";
echo "bye";
) | ftp -n -i;
};

函数调用
downlog ${Ip} ${Port} ${User} ${Pass} ${FileName} ${LocalName}

当然，如果你是多文件下载，例如做目录同步，建议使用lftp
lftp -u user,passwd -e "mirror -R ‘$path’ –ignore-time –verbose && quit" IP