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The Bash Trap Command

  If you've written any amount of bash code, you've likely come across the trap command. Trap allows you to catch signals and execute code when they occur. Signals are asynchronous notifications that are sent to your script when certain events occur. Most of these notifications are for events that you hope never happen, such as an invalid memory access or a bad system call. However, there are one or two events that you might reasonably want to deal with. There are also "user" events available that are never generated by the system that you can generate to signal your script. Bash also provides a psuedo-signal called "EXIT", which is executed when your script exits; this can be used to make sure that your script executes some cleanup on exit.
How to Count Files in a Directory in Linux?

How to Count Files in a Directory in Linux?

File counting in a directory is a common task that many users might need to perform. It could be for administrative purposes, understanding disk usage, or organizing files in a systematic manner. Linux, an open-source operating system known for its powerful command-line interface, offers multiple ways to accomplish this task. In this article, we'll explore various techniques to count files in a directory, catering to both command-line enthusiasts and those who prefer graphical interfaces.
Add a User to sudo Group in Debian 12 Linux

Add a User to sudo Group in Debian 12 Linux

In Linux systems, including Debian 12, the sudo group grants users the ability to execute administrative commands. This provides them with the privileges to install, update, and delete software, modify system configurations, and more. This article is intended for system administrators, advanced users, or anyone responsible for managing Debian 12 systems.
How to Check Battery Status Using Linux Command Line

How to Check Battery Status Using Linux Command Line

Checking the battery status through GUI is easy. Hovering the mouse cursor over the battery indicator given in the Laptop task bar simply shows the battery level. But, did you know you can find the battery status through the Linux command line as well? Yes, there are some utilities in Linux that can be of help in this regard. This article explains 4 different methods of checking laptop battery status using the Linux command line.
How to Search and Find Files for Text Strings in Linux

How to Search and Find Files for Text Strings in Linux

Searching for specific text strings in files is a common task in Linux. Whether you need to locate a file based on its content or search for a specific pattern within multiple files, Linux provides powerful command-line tools to assist you. In this guide, we will explore different approaches to searching and finding files for text strings in Linux, including the usage of the grep and find commands.

Pattern Matching In Bash

Wildcards have been around forever. Some even claim they appear in the hieroglyphics of the ancient Egyptians. Wildcards allow you to specify succinctly a pattern that matches a set of filenames (for example, *.pdf to get a list of all the PDF files). Wildcards are also often referred to as glob patterns (or when using them, as "globbing"). But glob patterns have uses beyond just generating a list of useful filenames. The bash man page refers to glob patterns simply as "Pattern Matching". First, let's do a quick review of bash's glob patterns. In addition to the simple wildcard characters that are fairly well known, bash also has extended globbing, which adds additional features. These extended features are enabled via the extglob option.
Running Multiple Linux Commands Simultaneously

Running Multiple Linux Commands Simultaneously

Understanding how to execute multiple commands at once in Linux can significantly improve your efficiency and productivity. This article will guide you through various ways you can run multiple Linux commands in a single line and even how to automate repetitive tasks.