How to use the output of the shell command in expect script's send

Question

I have a expect script written to perform a login operation. The login requires the 2fa code, this code can be obtained by executing the shell command 2fa my_login. Now how do I execute the 2fa command and pass it's output to the send of my script?

I need to do something like send -- "$(2fa my_login)". The output of the $(2fa my_login) should be passed to the send.

My script

#!/usr/bin/expect -f

set timeout -1

spawn /home/local/apps/forticlientsslvpn/64bit/forticlientsslvpn_cli --server vpn.vpn-domain.com:10443 --vpnuser user-id

expect "Password for VPN:"

send -- "pass\n"

expect "Enter the time-based OTP generated in your device."

send -- "$(2fa my_login)\n"

expect eof

Try ```send $(2fa my_login)``` or ```send "$(2fa my_login)"``` — Shimon Cohen, Aug 17 '20 at 08:51
No, it's not working. The first one throws errow and the second one throws variable not found — Santhosh Tpixler, Aug 17 '20 at 09:12
Expect uses the [Tcl language](http://www.tcl.tk/) which has different syntax from shell. You must learn Tcl to use Expect. If you are more comfortable with shell syntax you can try my [sexpect (Expect for Shells)](https://github.com/clarkwang/sexpect). — sexpect - Expect for Shells, Aug 17 '20 at 09:44
If you have to use Tcl, see [exec](http://www.tcl.tk/man/tcl/TclCmd/exec.htm) for how to run a command and get the output. — sexpect - Expect for Shells, Aug 17 '20 at 09:46
@SanthoshTpixler : _I have a expect script written to perform a login operation._ Since you want to extend your existing script, you should post it. From your description, we don't even know whether you use _Tcl/Expect_, or _sexpect_, or any other expect variety. — user1934428, Aug 17 '20 at 14:09
Thanks @sexpect--Expect_for_Shells I switched to sexpect and it was a breeze. — Santhosh Tpixler, Aug 17 '20 at 14:39

score 2 · Answer 1 · answered Aug 17 '20 at 14:43

Using the sexpect

#!/bin/bash

export SEXPECT_SOCKFILE=/tmp/sexpect-bc-iGciUZ.sock

sexpect spawn -close-on-exit /home/local/apps/forticlientsslvpn/64bit/forticlientsslvpn_cli --server vpn.vpn-domaincom:10443 --vpnuser user

sexpect expect  -glob "Password for VPN:"

sexpect send -enter -- "pass"

sexpect expect  -glob "Enter the time-based OTP generated in your device."

auth=$(2fa my_login)

sexpect send -enter -- $auth

sexpect wait

How to use the output of the shell command in expect script's send

1 Answers1

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