Welcome to LinuxScrew

A site for Linux lovers worldwide. For newbies, system engineers, administrators, and everybody in between. We cover all things Linux, plus various programming languages, including Python, Javascript, and PHP.

View our featured tutorials and projects in the slider below or scroll down to see all recent articles.

How to Convert a USB Printer to Wireless with a Raspberry Pi
How to Use a Raspberry Pi for Digital Signage
The Worst Things You’ll Probably Google As a Programmer on Linux
How to Build a Raspberry Pi Internet Kiosk
Browsing the Internet on a 1989 Macintosh II with a Web Rendering Proxy
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Variables in Bash/Shell Scripts and How To Use Them [Tutorial]

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Bash Variables and How to Use Them

This article will show you how to use variables in Bash and Shell scripts in Linux. Bash (or Linux Shell) scripts are files you write containing commands to automate common tasks and save yourself some time. Variables are things in scripts that hold a value for later use – a number, or a filename, or anything, really. Here’s how to define and use variables in Linux Shell scripts. These examples should work in the most popular Linux Shells, Bash, and Zsh. Declaring Bash Variables Bash VARIABLES ARE UNTYPED … Read more

jQuery vs JavaScript – Differences? Which is Better?

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jQuery vs JavaScript

This article will explain what JavaScript and jQuery are, how they differ, and how/why they should be used. What is JavaScript JavaScript began life in the mid-1990s as a scripting language for adding interactivity to web pages. Over time it has been developed into a full-featured programming language, which can even be run outside the web browser (more detail on this in our Node.js article). You can also see our article outlining the differences between JavaScript and Typescript here. What is jQuery? jQuery is a library written in JavaScript. … Read more

DIY Raspberry Pi/Python Powered PACHINKO [Kitchen Build]

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Raspberry Pi Python Pachinko

Pachinko? Pichinko? Pychinko? I’ve been playing around with is idea for a while because… I don’t know; it seemed like a cool concept. That’s my whole motivation. Here’s a Raspberry Pi and Python-powered pachinko machine. This project is really basic, so it’s good for beginners, and the result is a lot of fun to mess with and would make a good desk ornament to fidget with or something for the kids to build on a rainy day to learn about coding and circuits and all … Read more

How to Refresh the Page in JavaScript using location.reload(), With Examples

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JavaScript Refresh Page

Here’s a short guide to refreshing a webpage with JavaScript, with examples. There are over 500 ways to trigger a page reload using JavaScript. All but one are unofficial or are the side effect of another behavior. Here’s how to do it properly. Using location.reload() Simply call: location.reload() …anywhere in your code to trigger a page reload. It’s that easy. What about window.location.reload() ? You may see some use: window.location.reload() This is exactly the same as using location.reload() – the window object in JavaScript is the global context, so there’s usually no … Read more

Compare JavaScript Dates (Day/Minute/Hour/Before/After), With Examples

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JavaScript Compare Dates

Following on from our article on adding and subtracting time from dates in JavaScript – here’s how to compare two JavaScript date objects. This article will explore comparing dates/times with different granularity levels – from dates that are an exact month to dates that fall in the same year. Using Boolean Operators Native Javascript date objects can be compared using standard boolean/comparison operators – allowing you to compare dates by checking whether they are equal, not equal, greater than, less than, equal to or greater than, or equal to or … Read more

How to Use Functions in Bash/Shell Scripts, With Examples

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Bash Function Uses

This article will explain how to use functions in Bash scripts – helping you to reuse your code and simplify your scripts. Why write code multiple times when you can write it once and re-use it? That’s what functions let you do. This article outlines the use of functions in Bash/Shell scripts. What is a Function? A function is a piece of re-usable code. Functions can accept parameters, which allow them to perform the same repeatable actions on different inputs. Functions usually perform any action, output or print results, or return … Read more

Using the ‘sed’ Command in Bash/Linux, With Examples

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Bash sed command

The sed (Stream EDitor) command in Bash/Linux reads text from a stream or file and performs line-by-line operations on it based on a set of supplied criteria.  Here’s how to use it. sed is an automated way to process text. One simple example of where sed can be used is doing a simple find-and-replace for a word in a text document – the text with the words replaced can then be saved to a new file or overwrite the original. Why? Being able to modify text – either from a … Read more

Using the ‘sleep’ Function in Bash Scripts, with Examples

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Bash sleep Command

This article explains the sleep command in Bash/Shell scripts and how and why you might use it. The sleep command in Bash (and other Linux Shells) pauses execution for a specified amount of time – halting the script for a set number of seconds, minutes, hours, etc. Why Pause Execution? Why would you want to pause executing your script? Give the user a chance to interrupt an automated action Await user input Wait for a device to warm up/become available Stop text from flying across the screen if you’re trying to … Read more

Converting to Integer with JavaScript parseInt() [Examples]

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JavaScript parseInt

This article will show you how to use the parseInt() function in the JavaScript programming language. JavaScript is notoriously loosely typed – meaning that variables of one type (e.g., strings of text, numerical values, boolean values) are converted to others, allowing you to perform mathematical operations on strings and silly things like that. This causes all sorts of issues – strings containing numbers may not be parsed to the expected value, and all of a sudden, you have angry clients wondering why your shiny new … Read more

How to List Users and Groups in Linux, With Examples

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Linux List Users Groups

Linux supports multiple users and groups, allowing access to be granted to only the resources required.  Here’s how to list users, groups, and group membership. Separating users and groups ensures that different people can’t accidentally interfere with each other’s files and ensures system security by denying access to vital system files. This article details the various ways to query the users and groups on a computer running a Linux Operating System. Listing All Users The /etc/passwd file is a text-file database containing information on all of the users … Read more