/usr/bin/expect

# This line is if you want to use a file with the list of the commands.
# You'd need an authentication without password
# spawn sftp -b /home/daniele/Desktop/projects/pdf/script/cmdFile webdev@89.234.32.214

# This line is the simple login, instead
spawn sftp webdev@89.234.32.214
expect "assword:"

# You can send the password automatically if you feel confortable
# in writing it in this line
#send "My Password\n";

# Otherwise there is this more safe way (not automatic)
stty -echo
expect_user -re "(.*)\n"
send_user "\n"
send "$expect_out(1,string)\r"
stty echo

# At this point, we can expect two different replays
# depending if the password was correct or not.
expect {
        # This line "catches" the case you write a wrong password
        # In this case, we prefer to stop the process because the
        # re-tried password could be output in cleartext
        # Actually this issue could be handled in a better way
        "ermission" {
                puts "PLEASE, DON'T WRITE YOUR PASSWORD AGAIN"
                puts "RE-RUN THE PROGRAM, INSTEAD"
                exit
        }
        "sftp>" {
                send "\n";
        }
}
# Now the list of commands (in the case you are not using the first type of auth that is with the -b flag)
expect "sftp>"
send "cd /var/cc-pdfs/au-live/fault/\n";
expect "sftp>"
send "lcd /home/daniele/Desktop\n"

# command line argument
set in_arg [lindex $argv 0]
set get_command "get CC_$in_arg.pdf\n"
expect "sftp>"
send $get_command
expect "sftp>"
send "exit\n";