Learn Linux Shell Scripting - Fundamentals of Bash 4.4

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The idea of a function library is that you define functions that are shared between different scripts. These are repeatable, generic functions that do not care too much about the specific script to work. When you create a new script, the first thing you'll do, right after the header, is include the function definitions from the library. The library is nothing more than another shell script: however, it is only used to define functions, so it never calls anything. If you were to run it, the end result would be the same as if you had run an empty script. We'll start creating our very own function library first, before we look at how we can include it.

There is only one real consideration when creating a function library: where to put ...