当我们在终端下需要连接ssh时，ssh命令会提示需要手动输入密码，会显得很繁琐。当然你可以选择将本机的ssh公钥放入服务器~/.ssh/authorized_keys来实现免密码登录，这里介绍的是使用expect命令实现密码的自动输入。

1. 安装expect命令

   • OS X下安装

     brew install expect
     

   • Ubuntu下安装

     sudo apt-get install expect
     

2. expect使用示例

   • ssh自动登录脚本

     #!/usr/bin/expect
     # ssh to server
     log_user 0
     set timeout 10
     spawn ssh root@yourServer.com
     expect {
         "(yes/no)?" {
             send "yes\
     "
             exp_continue
         }
         "assword:" {
             send "yourPassword\
     "
         }
     }
     interact
     

   • scpto自动拷贝脚本

     #!/usr/bin/expect
     # ssh to server
     set timeout 10
     set to [lindex $argv 0]
     set from [lindex $argv 1]
     if { $to == "" || $from == "" } {
         send_user "Usage: rcpto to from"
         exit 1
     }
     spawn scp $to root@yourServer.com:$from
     expect {
         "(yes/no)?" {
             send "yes\
     "
             exp_continue
         }
         "assword:" {
             send "yourPassword\
     "
         }
     }
     interact
     

   • scpfrom自动拷贝脚本

     #!/usr/bin/expect
     # ssh to server
     set timeout 10
     set from [lindex $argv 0]
     set to [lindex $argv 1]
     if {$from == ""} {
         send_user "Usage: rcpfrom from \[to\]"
         exit 1
     }
     if {$to == ""} {
         set to [exec basename $from]
     }
     spawn scp root@yourServer:$from $to
     expect {
         "(yes/no)?" {
             send "yes\
     "
             exp_continue
         }
         "assword:" {
             send "yourPassword\
     "
         }
     }
     interact
     

3. expect脚本
   expect脚本是由tcl语言写成，详细语法可以参考expect帮助和tcl tutorial