December 2025
Intermediate to advanced
704 pages
15h 22m
English
Content preview from Linux Command Line and Shell Scripting Bible, 5th Edition
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Chapter 11Basic Script Building
Now that you’ve learned the basics of the Linux system and the command line, it’s time to start coding. This chapter discusses the basics of writing shell scripts. You’ll need to know these basic concepts before you can start writing your own shell script masterpieces.
Using Multiple Commands
So far you’ve seen how to use the command-line interface (CLI) prompt of the shell to enter commands and view the command results. The key to shell scripts is the ability to enter multiple commands and process the results from each command, even possibly passing the results of one command to another. The shell allows you to chain commands together into a single step.
If you want to run two commands together, you can enter them on the same prompt line, separated with a semicolon:
$ date ; whoSun Jun 01 15:36:09 EST 2025Christine tty2 2025-06-01 15:26Samantha tty3 2025-06-01 15:26Timothy tty1 2025-06-01 15:26user tty7 2025-06-01 14:03 (:0)user pts/0 2025-06-01 15:21 (:0.0)$
If you entered this code, congratulations, you just wrote a shell script! This simple script uses just two Bash shell commands. The date command runs first, displaying the current date and time, followed by the output of the who command, showing who is ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.