If you have one or more files that you need to send to a friend or store for a long time, compressing the files into a .zip archive is a good way to save on space and combine all files into a single object. If you need to keep the file contents private, for fear that they could be intercepted by the wrong party, or that someone could try to access them on your own system, then it is possible to add a password to your zip file. In this tutorial, you will learn how to zip files and add a password to your zip archive on a Linux system.
commands
inxi installation and usage on Ubuntu/Debian
The inxi Linux command can be used to see various system information and other handy bits of data right from your terminal. The command is ordinarily not installed by default. However, it is a small software package that provides access to the command, and it proves especially useful to system administrators and power users.
uname command in Linux with examples
The uname command in Linux is one of the frequently used commands. On Linux systems, there are a multitude of commands that can be used to print system information. We cover many of these commands in our guide about getting to know the hardware of your Linux box. One such command would be uname, which is especially good for listing information about the operating system itself and the Linux kernel that is running.
Send an email using Telnet
In this guide, we’ll show the step by step instructions to send an email using Telnet on a Linux system. This a great way to test your mail server configuration such as exim, sendmail or postfix without the need for an email client.
In this tutorial you will learn:
- How to install telnet on major linux distros
- How to send an email using Telnet protocol on Linux
Removing duplicate lines from a text file using Linux command line
Removing duplicate lines from a text file can be done from the Linux command line. Such a task may be more common and necessary than you think. The most common scenario where this can be helpful is with log files. Oftentimes log files will repeat the same information over and over, which makes the file nearly impossible to sift through, sometimes rendering the logs useless.
In this guide, we’ll show various command line examples that you can use to delete duplicate lines from a text file. Try out some of the commands on your own system, and use whichever one is most convenient for your scenario.
In this tutorial you will learn:
- How to remove duplicate lines from file when sorting
- How to count the number of duplicate lines in a file
- How to remove duplicate lines without sorting the file
Curl command not found
If you encounter the curl command not found on a Linux system, it means that the tool has not yet been installed. The curl Linux command can use various network protocols to download and upload data on Linux. In this tutorial, you will see how to install the curl command on all major Linux distributions.
How to crack a wireless WEP key using AIR Crack
This article shortly describes simple steps on how to crack a wireless WEP key using aircrack-ng software. This can be done by sniffing a wireless network, capturing encrypted packets and running appropriate encryption cracking program in an attempt to decrypt captured data. WEP ( Wired Equivalent Privacy ) is quite easy to crack as it uses only one key to encrypt all traffic.
Random Entropy in Bash
When using random numbers in Bash, the question of random entropy will sooner or later come up. This article will help you understand what entropy is, how it can be modified and optimized in Bash, and how it will affect random number generation.
In this tutorial you will learn:
- How to generate random entropy in Bash
- How to pre-seed the random number generator in Bash
- Examples demonstrating random entropy generation in Bash
Stat command: Usage and examples
The stat Linux command is one of the best ways to view the full details of any file that is stored on a Linux system. It is installed by default on all distributions, so there is nothing extra to install, and is basically a one stop shop for viewing file permissions, timestamp info like access times and modification times, and various other metadata for any file on your system. It also comes with a few handy options, allowing us to tailor the output for specific needs, and view information about all file types, including symbolic links, pseudo files, and others.
How to rollback pacman updates in Arch Linux
Arch Linux is often praised for it’s bleeding edge software and rolling release model. We discuss these features more in depth in our article comparing Arch Linux and Manjaro. In addition to this praise, arch linux also has a reputation for being unstable. This reputation stems from the sometimes unpredictable nature of bleeding edge software. The latest software from upstream developers may contain bugs that were not apparent during initial testing. As a result, the risk is always present that updating with the package manager, pacman, may bring about unexpected results. These may include a specific piece of software no longer working properly (or at all) or even multiple applications or Desktop Environments no longer working as expected.
Introduction to the Systemd journal
Systemd is nowadays the init system adopted by almost all Linux distributions, from Red Hat Enterprise Linux to debian and ubuntu. One of the things that made Systemd the target of a lot of critics is that it tries to be a lot more than a simple init system and tries to re-invent some Linux subsystems.
The traditional logging system used on Linux, for example was rsyslog, a modern version of the traditional syslog. Systemd introduced its own logging system: it is implemented by a daemon, journald, which stores logs in binary format into a “journal”, which can be queried by the journalctl utility.
In this tutorial we will learn some parameters we can use to modify the journald daemon behavior, and some examples of how to query the journal and format the output resulting from said queries.
In this tutorial you will learn:
- How to change default journald settings
- How journald can coexist with syslog
- How to query the journal and some ways to format the queries output
Falling back to the standard locale – Solution
If you are trying to use the perl command in your terminal or execute a script coded in the language, you may encounter the Falling back to the standard locale error. This indicates that your Linux system is missing a particular software package that Perl relies on, or the software has become corrupted or misconfigured. In this tutorial, we will show you how to remedy the error and get your perl command working again.