
Linux Command Line and Shell Scripting Techniques
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Variables are great since they can hold any value that we can think of. Often, we need more than just holding a value inside a variable. In this recipe, we are going to deal with a lot of different things that we can do to a variable, sometimes changing it and sometimes completely replacing it.
In order to be able to change variables, you will need to understand one simple concept. bash
cannot change the variable itself; we are going to mention this a little later, but if you need to change something in a variable, you will have to reassign it.
There is a lot of things that can be done to a variable. Sometimes, we want to know more about what it contains; sometimes, we need to change something in order to use it later; or, we may simply want to know if the variable even has a value.
In this recipe, we are going to use the command line a lot since it makes explaining things much easier.
Before...
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