Expect - Revision history

Heath at 15:14, 10 May 2019

2019-05-10T15:14:53Z

Heath at 15:14, 10 May 2019

2019-05-10T15:14:25Z

Goldbolt: Created page with "Expect is a program that talks to other interactive programs according to a script. Following the script, Expect knows what can be expected from a program and..."

2019-01-07T13:08:16Z

Created page with "<strong>Expect</strong> is a program that talks to other interactive programs according to a script. Following the script, Expect knows what can be expected from a program and..."

New page

<strong>Expect</strong> is a program that talks to other interactive programs according to a script. Following the script, Expect knows what can be expected from a program and what the correct response should be. An interpreted language provides branching and high-level control structures to direct the dialogue. In addition, the user can take control and interact directly when desired, afterward returning control to the script.

=ssh=
Expect can be used to do most things. Setting up ssh to auto connect using a command, such as "jump", will automatically connect you to a secure shell if set up properly.

The first script is a basic bash script which, then, calls to the expect script:

#!/bin/sh
jumper PASSWORD 12.345.67.89 USERNAME

This bash script calls to the <code>jumper</code> expect script:

#!/usr/bin/expect -f
# set Variables
set password [lrange $argv 0 0]
set ipaddr [lrange $argv 1 1]
set user [lrange $argv 2 2]
# now connect to remote UNIX box (ipaddr) with given script to execute
spawn ssh $user@$ipaddr
match_max 100000
# Look for passwod prompt
expect "*?assword:*"
# Send password aka $password
send -- "$password\r"
interact

These both have to be set to executable by the owner of the files or by global with <code>chmod</code> and placed somewhere they are able to execute it from, e.g. /bin/.

← Older revision		Revision as of 15:14, 10 May 2019
Line 26:		Line 26:

	These both have to be set to executable by the owner of the files or by global with <code>chmod</code> and placed somewhere they are able to execute it from, e.g. /bin/.		These both have to be set to executable by the owner of the files or by global with <code>chmod</code> and placed somewhere they are able to execute it from, e.g. /bin/.
−
−	Autoexpect is a built-in script with expect that auto-generates an expect script from watching a session, basically autoexpect watches you interacting with another program and creates an Expect script that reproduces your interactions.
−
−	~~just type <code>autoexpect</code> and a new session will start. autoexpect will then begin recording your interactions until you stop it.~~
−
−	This has the downside of recording full output and putting them into an expect field. This can be avoided by using the <code> - p </code> flag which will put auto expect into prompt mode. In this mode, autoexpect will only look for the the last line of program output - which is usually the prompt. This handles the date problem (see above) and most others.

← Older revision		Revision as of 15:14, 10 May 2019
Line 26:		Line 26:

	These both have to be set to executable by the owner of the files or by global with <code>chmod</code> and placed somewhere they are able to execute it from, e.g. /bin/.		These both have to be set to executable by the owner of the files or by global with <code>chmod</code> and placed somewhere they are able to execute it from, e.g. /bin/.
		+
		+	Autoexpect is a built-in script with expect that auto-generates an expect script from watching a session, basically autoexpect watches you interacting with another program and creates an Expect script that reproduces your interactions.
		+
		+	just type <code>autoexpect</code> and a new session will start. autoexpect will then begin recording your interactions until you stop it.
		+
		+	This has the downside of recording full output and putting them into an expect field. This can be avoided by using the <code> - p </code> flag which will put auto expect into prompt mode. In this mode, autoexpect will only look for the the last line of program output - which is usually the prompt. This handles the date problem (see above) and most others.