Can the expect script continue to execute other command after "interact"?

Question

I am writing a script to run ssh so as to login a remote host, after all the operation is done, I type exit and log off. But I want the script to continue running and write log on the local host. The script is something like:

#!/usr/bin/expect
spwan ssh qwerty@remote_host

expect {
    "password:" {
        send "123123\r"
    }
}

interact;
send "echo $(date) >> login_history.log\r"

But the last command "send ..." always failed with the error message like "send: spawn id exp4 not open ..."

When I log off from the remote host, can the expect script continue to work as it is running on the local host?

Cameron Laird Cameron Laird · Accepted Answer · 2011-09-27T13:24:13

YES, processing can continue after an [interact].

Short answer: change the last {send ...} to {exec date >> login_history.log}

There are several concepts you'll want to understand to achieve the control flow you're after. First, http://www.cotse.com/dlf/man/expect/interact_cmd_desc.htm provides a succinct synopsis and example of intermediate [interact] use.

Second: why did you see the message "... spawn id ... not open ..."? Because the spawn id is not open. The script you wrote said, in effect, "interact, then, after interact is over, send a new command to the ssh process." If you've already logged out, then, of course that id for a defunct process is no longer available.

Third: how do you achieve what you want? I'm unsure what you want. It sounds as though it would be enough for you simply to transform the [send] as I've described above. How does that look to you?

Can the expect script continue to execute other command after "interact"?

1 Answers