Bash Script Comment Example

How to write comments in Bash Scripts

Well you have written an awesome Bash script. It works perfectly and perhaps there is no need to add new functionality. Well, maybe not for now, at least! At this stage you are happy with the script. However, after few months you reopen your bash script again to add new feature and you get a headache to figure out on how the script actually works. Hence, you need to spend additional energy and time before you can actually start editing the script in order to add new feature.

Well, at this point you regret that you did not put some comments ( notes ) into the script to remind you of how the bash script is structured. Not only that Bash comments serve as excellent notes for you or anybody else who might work with your script they may be to some extend also used as a basic bash script debugging tool.

In this tutorial you will learn:

  • How to comment on bash command line
  • How to write comment bash scripts
  • How to create multiple line comments

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Hello World example with Ruby.

How to install ruby on RHEL 8 / CentOS 8

Ruby is a very flexible scripting language, it’s popularity well-earned by it’s power. In this tutorial we will install Ruby on a RHEL 8 / CentOS 8, and write the famous “Hello World” program to test that our installation is working as intended. Note however, that with all languages, Ruby’s capabilities are far more than simple text printing on the command line.

In this tutorial you will learn:

  • How to install Ruby with dnf
  • How to get Ruby version information
  • How to write and run the “Hello World” example program in Ruby

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Successful cpan perl module install with cpan on RHEL 8

How to install cpan on RHEL 8 / CentOS 8

Perl is a well-known programming language with long development history. The same long history provides the countless modules written in it, and distributed in various channels throughout the World Wide Web. As with most programming languages, if you implement something that you find useful, and maybe write it in a generic way, there are high chances others would find it useful too.

If you share your work with others, they don’t need to re-implement the wheel, they can spend time on other tools, thus making the community as a whole richer, and we have found the spirit of open source with a short walk. But as many people write perl modules, and perl runs on just about anything, it can be hard to find the module you are looking for, let alone build it in your environment. And that’s where cpan comes into play. CPAN itself is a large perl module repository, the cpan tool is a client that is able to fetch and compile needed modules to the local system.

In this tutorial we’ll install cpan on a RHEL 8 / CentOS 8, run the initial configuration, and install a module with this tool’s help.

In this tutorial you will learn:

  • How to install cpan
  • How to run initial configuration
  • How to install a perl module with cpan

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Bash Terminal

How to Debug Bash Scripts

There are techniques from traditional programming environments that can help.
Some basic tools like using an editor with syntax highlighting will help as well.
There are builtin options that Bash provides to make debugging and your everyday Linux System Administration job easier.

In this article you will learn some useful methods of debugging Bash scripts:

  • How to use traditonal techniques
  • How to use the xtrace option
  • How to use other Bash options
  • How to use trap

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Check Python Version on Ubuntu Linux System

Check Python Version

The following article will provide you with the information on how to check Python Version on your operating system. You will learn how to check for python version using the python command as well as how to determine the python version programmatically, from python console and using python script.

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