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The Vim editor (and its predecessor, vi) is a command line editor for Linux systems. It has a long standing reputation as being the most powerful text editor on Linux. After mastering it, many users will even claim that it is far speedier and more convenient to use than a typical GUI editor packed with lots of features in its menus.

Vim has a staggering number of features and functions, but they are all hidden behind keyboard shortcuts and commands. There are no menus or hints in Vim, as users are expected to have enough of a grasp to navigate around on their own. And this is where Vim’s learning curve turns off most new users from bothering with it. Many novices would rather stick with something simple, like nano, than deal with all Vim’s depth.

On Linux-based operating system the /etc directory is used to hold global configuration files for applications and services. A good set of configurations is really important for a good working system, so being able to keep track of changes and quickly revert them, in case something go wrong, is crucial. Etckeeper helps us achieve this goal keeping configuration files under version control.

If you want to retrieve stock quotes and crypto price data, you do not even need to leave your command line terminal. In this tutorial, we will show you how to use a Bash script to get stocks and crypto pricing on a Linux system.

DAAP server is an Apple Inc. proprietary protocol to share media files over the network. DAAP server allows share media files among network connected devices where the central media share repository resides on main server. In this simple tutorial we will be installing and configuring DAAP server share using forked-daapd media server with support for RSP, DAAP, DACP and AirTunes on Ubuntu Linux or any other Debian Linux based system.

There is no need to install tons of software in order to create a nice and informative presentation. tpp, which stands for Text Presentation Program is a simple to use command line presentation tool which allows you to create a fancy text based slide show presentation and share it with your colleagues or students as an ordinary ASCII text file. tpp utilizes ncurses, and it supports colors, slide-in, source code output, animated command line execution and a real time command executions all available from within your terminal.

The ability to automate tasks with Bash scripts in Linux is one of the operating system’s most powerful components. However, due to the sheer amount of scripting components, it can be intimidating for newcomers. Even longtime users may forget something every once in a while and that is why we have created this Bash scripting cheat sheet.

If you have any experience on the Linux command line, then you should have run into command flags, which help us modify the behavior of a command that we are executing.For example, if we execute the ls -l command, the -l part of the command is a flag that we are passing as an argument to ls. This same functionality can be used in a Bash script, allowing us to pass some input to the script through flags when we are executing the script.

Normally, a Bash script will execute each line of code the moment it reaches it, then immediately move on to the next. But it is also possible to add pauses to a Bash script in order to delay it or allow the user time to respond to a prompt, etc.

UEFI is the firmware interface which on modern machines has superseded the legacy BIOS. One of the features of the UEFI firmware is being able to store boot entries in the persistent and editable NVRAM memory (Non Volatile RAM). While installing a Linux distribution (or any other operating system) in UEFI mode makes usually the related boot entry to be written to the NVRAM, in some cases we may want to perform manual operations such as modifying the boot order, creating or deleting a boot entry.

A loop device is a pseudo-device which doesn’t correspond to a real, physical block device, but can be used to make a file appear and be treated like one. To manage loop devices on Linux, we can use the losetup command: the utility let us create new loop devices, detach them and retrieve information about existing ones.

Qcow2 is the default virtual disk storage format used by Qemu (qcow stands for qemu copy-on-write). This image format makes use of thin provisioning, so, after we initially set the maximum virtual size of a disk, space is actually allocated only when used, but not made available back to the host when freed.In this article we see how to “sparsify” a qcow2 disk image to reclaim available space, how to expand it or shrink it, and how to manage the partitions layout on it from the host system, connecting it by using the NBD protocol.

In a previous article, we saw how to create kvm virtual machines from the command line; in this tutorial, instead, we learn how to access and modify virtual machines disk images, using some utilities which are part of the libguestfs package on the most commonly used Linux distributions. Those tools let us perform a variety of tasks.

When using Linux on mobile devices such as Laptops, it is very important to tune the right kernel parameters in order to optimize battery life. Tlp is a highly customizable, free and open source command line utility released under the GPLv2 license (the source code is hosted on github) created with this exact goal. In this tutorial we see how to install Tlp on some of the most used Linux distributions, and how to configure it.

Vim is one of most used and famous text editors on Linux and other Unix-based operating systems. It is free and open source software, based on the original Vi editor (Vim stands for Vi IMproved) and mainly developed by Bram Moolenaar. The editor can be setup by editing the ~/.vimrc configuration file, and by using a vast range of plugins. In this article we see how to improve and customize the Vim status bar by installing Powerline, a nice plugin written in Python which can be also used to customize the Bash and Zsh shell prompts.

If you already have some experience as a Linux system administrator, chances are you know what cron is and what it does. If you’re just starting working with Linux, it’s essential knowledge that will certainly serve you later. Either way, if you already have the knowledge, this article will refresh it. If not, you will get a guide to start you up. So you’re only expected to have some basic knowledge of Linux systems and, as usual, a desire to learn.

When performing digital reconnaissance or penetrating testing, it’s important to fingerprint a network by understanding what operating system is used on a remote a host. Nmap is a great tool for this job. Although normally associated with the cybersecurity field and penetration testing, Nmap can also be used for benevolent purposes, such as a system administrator taking an inventory of what operating systems all the systems on his network are running.

In a previous tutorial we saw the basic concepts behind the usage of Tkinter, a library used to create graphical user interfaces with Python. In this article we see how to create a complete although simple application. In the process, we learn how to use threads to handle long running tasks without blocking the interface, how to organize a Tkinter application using an object oriented approach, and how to use Tkinter protocols.

Tkinter stands for “Tk interface”: the package with the same name on many Linux distributions provides the Python bindings for the Tcl/Tk GUI toolkit. Although other graphical toolkit can be used from Python, like Qt or GTK, Tkinter is the standard (the Python IDLE editor and development environment is written using this toolkit, for example) and probably the easiest to work with. In this tutorial we see the basic concepts behind the usage of Tkinter and how to create and interact with some of the most used widgets.

The Z-shell (zsh) is a modern and very powerful shell: it incorporates and extends many feature of other shells, like Bash. Although it can be used as a powerful scripting language, it is mainly aimed at interactive use, since one of its more prominent feature is the advanced tab completion system. In this tutorial we see how to install zsh in the most commonly used Linux distributions, see what are its startup and shutdown files and how to perform the basic configurations.

Linux Unified Key Setup (LUKS) is the de-facto standard block device encryption format used on Linux-based systems. We already discussed some of the features provided by it in a previous tutorial about using a file as a LUKS device key. When using LUKS, encryption metadata is stored on the header which is created at the beginning of the encrypted device (a copy of the header is created at end of the device for redundancy, when using LUKS2).If desired, it is possible to specify that the header should be detached from the device: in this tutorial we see how.