Running a program continuously (forever) using looping constructs or recursion
So far, this cookbook has mostly shown scripts that serve a single purpose and exit upon task completion. This is great for single use scripts, but what about if we wanted to have scripts execute multiple scripts through a menu, or perform tasks in the background automatically forever without being executed each time by scheduling processes (like cron)? This recipe introduces a few ways for a script to run forever until it is killed or exits.
Getting ready
Besides having a terminal open, we need to remember a few concepts:
- Recursive functions combined with a prompt (for example, the
read
command) can result in a script that loops based on user input - Looping constructs such as
for
,while
, anduntil
can be executed in such a way that a condition is never met and cannot exit
Therefore, a loop or something that causes a loop will force a program to run for an indefinite period of time until an exit event occurs.
Note
In...