In this article, let us review how to use Unix tac command, rev command, paste command, and join command with practical examples.
Question: Is it possible for me to combine multiple sed commands? Can I combine two sed commands and execute it as single sed command?
Answer: In our previous articles we learned sed with single commands — printing, deletion, substitute and file write.
In this article let us review how to combine multiple sed commands using option -e as shown below.
Question: I like Vi style of editing and I’m very comfortable with Vi commands. How do i use Vi style line editing in Unix command line?
Answer: Execute set -o vi at your Unix shell to enable Vi style editing.
Debian based systems (including Ubuntu) uses apt-* commands for managing packages from the command line.
In this article, using Apache 2 installation as an example, let us review how to use apt-* commands to view, install, remove, or upgrade packages.
From Vim editor, move your cursor to a number and press Ctrl+A to increase the number or Ctrl+X to decrease the number.
- Ctrl+A to increase the number under cursor
- Ctrl+X to decrease the number under cursor
Question: How do I find out what Unix shell I’m currently running? Can you also explain how can I change my Unix shell both temporarily and permanently? (For example, from bash to tsh).
Answer: You can achieve these using $0, exec, chsh -s. In this article, let us review how to do these in detail.
Question: I would like to understand the basics of how to write and execute a pascal program on Linux OS. Can you explain it with a simple example?
Answer: In this article, let us review very quickly how to write a basic Hello World pascal program and execute *.p or *.pas program on Linux or Unix OS.
This article is part of Unix Sed Tutorial series. In previous articles, we discussed about sed print operation , sed delete operation and sed find and replace.
In this article, let us review how to extract part of one file and write it to another file using sed.

My name is Ramesh Natarajan. I will be posting instruction guides, how-to, troubleshooting tips and tricks on Linux, database, hardware, security and web. My focus is to write articles that will either teach you or help you resolve a problem. Read more about