将变量传递给 Expect 和 Spawn

Question

I'm writing a script that will scp a tar file from my local server to a remote host. Since the script generates the file through a pre-requisite process, the name is generated dynamically. My script needs to take the name of the file and pass it to scp for transfer.

#!/usr/bin/expect -f

spawn scp test.$(date +%y%m%d_%H%M).tar user@IP-ADDRESS:/destination/folder
set pass "password"
expect "password: "
send -- "$pass\r"
expect eof

I've tried setting the filename as a variable but keep seeing the same error:

can't read "(date +%y%m%d_%H%M)": no such variable while executing "spawn scp test.$(date +%y%m%d_%H%M).tar user@IP-ADDRESS:/destination/folder"

Answer 1

$(date +%y%m%d_%H%M) is not a Tcl command. If you use expect , you have to learn Tcl. To get a formatted date in Tcl, use the clock command. Also, interpolation of the result from a command in Tcl is not done by $(....) , but by [....] . You can find examples for this construct here .

Answer 2

Decided to go another route since the team was able to provision a new Artifactory repo for this binary and alike. However, to the advice provided here I was able to make a few discoveries which I used to fix my issues:

I also had a password with $ symbol and that also caused a world of issues.

#!/bin/bash

TEST=$(date +%y%m%d_%H%M)
/usr/bin/expect <<eof

set password {pas\$word}
spawn scp "$TEST" user@IP-ADDRESS:/destination/folder
expect "*password:"
send "$pasword\r"
expect eof