Script analyzer


One of the best things about the command-line shell is that when you find yourself typing the same commands over and over, or when you know you're going to iterate over a command dozens of times, you can dump the whole thing in a script that can be run again and again. Thanks to the way many shells are structured, you don't need to be much of a programmer to get any of this to work,. You can often paste a few commands into a script without knowing anything other than #!/bin/bash and that a return signal of 0 means a command executed correctly, rather than incorrectly. (Don't forget that with if statements!) As time goes on, however, scripts will often get augmented with other bits of code, and before long, they've become a vital part of your personal or professional infrastructure. That's when you need to start looking at their contents more seriously.

ShellCheck is a script-checking tool that's intended for beginners but also happens to be useful for solutions that have outgrown their initial single use cases. It's also a great way to improve your script knowledge. It can be run via an online form, and even from within your favorite script editor, but it's often simpler to start with the command itself by passing your script as its only argument. If you get no advice, then ShellCheck has found nothing drastically wrong with your script, but that's unlikely because ShellCheck is very good at identifying errors. It warns you when you don't use a variable, when you should be using double quotes, when to remove dashes, and when to add a return case, alongside dozens of other typing, portability, style, and conditional errors. And unlike some of the scripts we tested, it works perfectly.

Project Website

If you write any sh, bash, dash, or ksh scripts, ShellCheck will offer suggestions on how to improve them.

Terminal mathematics

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