Exiting the loop with break and continue

This gives us some nice opportunities, such as infinite loops:

while true ; do echo "Hello" ; done

Since true always evaluates as true, the condition is always verified so we have an infinite execution of the do/done clause; press Ctrl+ C to exit from the loop. An infinite loop looks like something nasty, but it opens a new scenario for our scripts, since we can make them run or wait for something for as long as we want. Actually, if we do not use a couple of loop control commands: break will exit the loop and continue will restart it, jumping over the remaining commands. Let's see an example of creating a hypothetical backup program menu:

#!/bin/bash
while true
do
  clear
  cat <<MENU
  BACKUP UTIL v 1.0
  ------------------
  1. Backup a file/directory
  2. Restore a file/directory
  0. Quit
  ------------------
MENU
  read ...