参数说明：
-r：拷贝目录
-c：允许压缩

执行脚本：

#!/usr/bin/expect -f
set password 密码
#download
spawn scp root@ip:/root/a.wmv /home/yangyz/
set timeout 300 
expect "root@ip's password:"
set timeout 300 
send "$password\r"
set timeout 300 
send "exit\r"
expect eof

#upload
spawn scp /home/xxx.sql root@ip:/root/xxx.sql 
set timeout 300 
expect "root@ip's password:"
set timeout 300 
send "$password\r"
set timeout 300 
send "exit\r"
expect eof