Shell script for telnet and run commands

Issue

I have made a shell script which can telnet automatically and run commands on the other machine and end the telnet session without any interact from the user, only he just run the script or call it from another script.
but you need to install EXPECT and TCL packages on your Unix system.
The script contains the following instructions:


#!/usr/local/bin/expect -f ####/usr/local/bin/expect is the directory where expect was installed
log_user 0 ####this command is used to hide the conversation between the script and the other machine
set address [lindex $argv 0] ###assign the first passed parameter while calling the script to $address
set username [lindex $argv 1] ###assign the 2nd passed parameter while calling the script to $username
set password [lindex $argv 2] ###assign the 3rd passed parameter while calling the script to $password
spawn telnet ${address} ###start the telnet session to machine with IP=$address

###start conversation with the machine:
expect "login:"
send -- "${username}\r"
expect "Password:"
send -- "${password}\r"
expect "$ "
send -- "#!/bin/ksh\r" ###declare the shell to be used (optional)
expect "$ "
send -- "###type her any command you want to execute"
expect "$ "
send -- "exit\r" ###end the telnet session and exit the script


To execute this script, I typed:
$ expect_script "address" "username" "password" ###the script name is "expect_script"
but before u call the expect script, you should make the expect script executable, and this can be done by typing:
$ chmod +x expect_script

Solution

Try this:

#!/usr/local/bin/expect 
spawn telnet <machine ip> 
expect "login:" 
send "<username>\n" 
expect "Password:" 
send "<password>\n" 
send "bash\n" 
send "cd /opt\n" 
send "ls -ltr\n" &#61664; (if you are not giving \n then it will wait for your response or u have to type enter manually). 
interact 

How to execute the “expect“ command expect –f <file name>
Ex: expect –f <filename>.expect

Note

Thanks to ZooZoo for this tip on the forum.