Learn Linux Shell Scripting - Fundamentals of Bash 4.4

Loop control and nesting

For the final part of this chapter, we'd like to show you how you can influence nested loops with loop control as well. Both break and continue will take an extra argument: a number that specified which loop to break out of. By default, if this argument is omitted, it is assumed to be 1. So, the break command is equal to break 1, and continue 1 is the same as continue. As stated before, we can theoretically nest our loops as deep as we want; you're likely to hit logical issues a lot earlier than problems with the technical capabilities of your modern system! We'll look at a simple example that shows us how we can use a break 2 to not only break out of a for loop, but out of the outer while loop as well:

reader@ubuntu:~/scripts/chapter_11$ ...