linux 腳本之 expect命令使用
1 概述
expect 是由Don Libes基於Tcl(Tool Command Language )語言開發的,主要應用於自動化交互式操作的場景,借助Expect處理交互的命令,可以將交互過程如:ssh登錄,ftp登錄等寫在一個腳本上,使之自動化完成。尤其適用於需要對多臺服務器執行相同操作的環境中,可以大大提高系統管理人員的工作效率
2 語法
expect命令
expect 語法:
expect [選項] [ -c cmds] [ [ -[f|b] ] cmdfile] [ args]
選項
-c:從命令行執行expect腳本,默認expect是交互地執行的
示例:expect -c ‘expect "\n" {send "pressed enter\n"}
-d:可以輸出輸出調試信息
示例:expect -d ssh.exp
expect中相關命令
spawn:啟動新的進程
send:用於向進程發送字符串
expect:從進程接收字符串
interact:允許用戶交互
exp_continue匹配多個字符串在執行動作後加此命令
expect最常用的語法(tcl語言:模式-動作)
單一分支模式語法:
expect “hi” {send “You said hi\n"}
匹配到hi後,會輸出“you said hi”,並換行
多分支模式語法:
expect "hi" { send "You said hi\n" } \
"hehe" { send “Hehe yourself\n" } \
"bye" { send “Good bye\n" }
匹配hi,hello,bye任意字符串時,執行相應輸出。等同如下:
expect {
"hi" { send "You said hi\n"}
"hehe" { send "Hehe yourself\n"}
"bye" { send “Good bye\n"}
}
3 腳本
以下是在expect在shell腳本中調用常用的幾個用法,自動拷貝腳本,下發腳本,ssh 和telnet 連接遠程主機.
#!/bin/bash # #****************************************************************************** #Author: Sunny #Date: 2017-09-03 #FileName: scp.sh #version: 1.0 #Your change info: #Description: For #Copyright(C): 2017 All rihts reserved #***************************************************************************** echo "1 copy wang home dir,usage:$0" echo "2 copy file under wang home,usage: $0 file_to_copy" echo "3 send file to wang home,usage: $0 file_to_send" echo "4 login other host by ssh,usage: $0 login_ip" echo "5 login other host by telnet,usage: $0 login_ip login_user" read -p "input the remote ip: " ip read -p "input full path file_name or dir: " file read -p "input host password: " passwd read -p "Please input your choice: " choice case $choice in 1) expect -c " spawn scp -r [email protected]$ip:$file "$file\_$(date +%F-%H-%M)" expect { # \"*assword\" {set timeout 300; send \"$passwd\r\"; } \"*assword\" {set timeout 300; send \"$passwd\r\"; } \"yes/no\" { send \"yes\r\"; exp_continue; } } expect eof" ;; 2) expect -c " spawn scp [email protected]$ip:$file /root/ expect { # \"*assword\" {set timeout 500; send \"$passwd\r\"; } \"*assword\" {set timeout 500; send \"$passwd\r\"; } \"yes/no\" { send \"yes\r\"; exp_continue; } } expect eof" ;; 3) expect -c " spawn scp $file [email protected]$ip:/root expect { # \"*assword\" {set timeout 500; send \"$passwd\r\"; } \"*assword\" {set timeout 500; send \"$passwd\r\"; } \"yes/no\" { send \"yes\r\"; exp_continue; } } expect eof" ;; 4) expect -c " spawn ssh $ip expect { \"yes/no\" { send \"yes\r\"; exp_continue; } \"*assword\" {set timeout 500; send \"$passwd\r\"; } } interact expect eof" ;; 5) expect -c " spawn telnet $ip expect { \"*assword\" {set timeout 500; send \"$passwd\r\"; } \"login\" { send \"sunny\r\";exp_continue; } } interact expect eof" ;; *) echo "Your input is wrong,please check" exit ;; esac
4 總結
expect可以實際靜默的操作,這個在腳本中經常用到,讀者根據對應的功能,拷貝相關代碼,可以直接把變量換成固定的值,不需要每次運行腳本都需要人工輸入變量值,實現靜默操作。
本文出自 “自學linux” 博客,請務必保留此出處http://ghbsunny.blog.51cto.com/7759574/1963007
linux 腳本之 expect命令使用