Question

我正在尝试将一个expect脚本ssh到远程系统中，并获取远程命令的输出。我希望在本地提供该输出。例如，ssh进入系统并获得本地时间输出：

#!/usr/bin/expect --
set timeout 60
spawn ssh user@server.domain.com
expect {
timeout {puts "timed out after $timeout seconds"; exit}
"Password:"
}
send "SuperSecretPassword\r"
expect "user$ "
send "date\r"
expect "date"
expect "\r"
set buffer1 '$expect_out(buffer)'
expect "\r"
set buffer2 '$expect_out(buffer)'
send "exit\r"
expect eof
set buffer3 '$expect_out(buffer)'
exit
export VARIABLE $buffer1
export VARIABLE $buffer2
export VARIABLE $buffer3
echo "Okay, we are done expecting..."
echo "Buffer1: $buffer1"
echo "Buffer2: $buffer2"
echo "Buffer3: $buffer3"

当然，上面的方法不起作用，实际上脚本执行在期望“退出”之后结束

Answer 1

#!/usr/bin/expect --
log_user 0
set timeout 60
spawn ssh user@server.domain.com
expect {
timeout {puts "timed out after $timeout seconds"; exit}
"Password:"
}
send "mypassword\r"
expect "user$ "
send "date\r"
expect "date\r\n"
expect "*\r" { send_user "$expect_out(0,string)\n" }
close
exit

Answer 2

将数据从子进程（期望脚本）传递到父进程（shell脚本？）的方法是通过stdio通道：expect脚本必须打印expect_out缓冲区，shell脚本必须捕获期望输出并以某种方式对其采取行动。

在exit之前

执行类似

的操作

puts "buffer1='$buffer1'"
puts "buffer2='$buffer2'"
puts "buffer3='$buffer3'"

您可能希望关闭所有其他预期输出。那是log_user 0和......我不记得的其他东西...... Exploring Expect书中有很多精彩的细节。

shell脚本可以

expect_out=$(./program.exp)
while read line; do
    [[ $line == buffer[123]=* ]] && eval "$line"
done <<< "$expect_out"

或者可能只是

source <(./program.exp)

当然，expect本身就是一种功能完善且功能强大的语言（Tcl），毫无疑问可以完成你需要做的所有本地工作，而不必费心去调用期望并传回数据的shell脚本

期望进入远程系统，获得输出到本地shell变量

2 个答案: