AWK is a powerful pattern scanning and processing language developed by Alfred Aho, Peter Weinberger and Brian Kernighan at Bell Labs - the name of this tool is indeed derived by concatenating the letter of their surnames to one another. It is one of that tools that every Linux professionals (not only the more seasoned ones) must be skilled on, since it is broadly used in a lot of shell scripts that very often are inherited from predecessors and that must be maintained: the sad truth is that very often is not worth the effort to rewrite them using other more modern languages, so knowing how to deal with it can really ease your life. And anyway, ... sometimes it requires much less time to code an AWK one liner than a Python script, so knowing how and when to use AWK is certainly a valuable skill still nowadays.
The aim of this post is not to provide a complete explain about how to code with AWK - there are more modern and handy languages such as Python nowadays: I just want to provide a very quick yet comprehensive walkthrough on it focusing on how to write AWK one-liners that are often embedded in shell scripts or that you can use to sort out common system administration tasks. That's why I'm also showing some real-life use cases with AWK one-liners that can very quickly and easily sort things out.

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