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Sed Command in Linux - Print Lines in a File

Here is the brief introduction of the Super sed:

  • sed stand for Stream EDitor and it being based on the ed editor, it borrows most of the commands from the ed. It was developed by Lee E. McMahon of Bell Labs.
  • sed offers large range of text transformations that include printing lines, deleting lines, editing line in-place, search and replace, appending and inserting lines, etc.
  • sed is useful whenever you need to perform common editing operations on multiple lines without using 'vi' editor.
  • Whenever sed is executed on an input file or on the contents from stdin, sed reads the file line-by-line and after removing the trailing newline, places it in the "Pattern space", where the commands are executed on them after conditions (as in case of regex matching) are verified, and then printed on the stdout.

Printing Lines from a File using sed

Before we start, just remember two points:

  1. sed "p" command lets us print specific lines based on the line number or regex provided.
  2. sed with option -n will suppress automatic printing of pattern buffer/space. So, we would want to use this option. (Explained in later section)

Read more at YourOwnLinux


Essential commands for text manipulation/filtering to be known a linux user

A useful list of unix commands every linux user should know which enables to do almost any kind of text filtering/manipulation.


Google's New 'Password Alert' Extension Another Step To Protect Against Phishing Attempts

Google's New 'Password Alert' Extension Another Step To Protect Against Phishing Attempts

Google has taken another step toward protecting users from fishing attempts by releasing a new Google Chrome extension 'Password Alert'. The extension protects users from being gmail account overused with other non-google websites. As soon as it detects that the password has been exposed to any non-google website/service, it prompts to reset password immediately. 

Read At LinuxAndUbuntu


100 Essential Free Apps

We can all admire the vast number of open source apps and tools that are available on modern operating systems. They come in all shapes and sizes. Small console tools that can be easily integrated into large projects, feature-rich apps that offer everything bar the the kitchen sink, well designed tools, and eye catching candy. Open source software holds numerous compelling advantages over proprietary software.

The 100 applications are divided into 5 sections: Work, Internet, Multimedia/Games, Tools, and Development/Science. You will probably have heard of many of the applications, but I'm pretty sure there will be many absorbing projects for you to discover.

<A HREF="">Full article</A>


Microsoft Visual Studio Code for Linux. What do you think?


A few days ago, Microsoft released Microsoft Visual Studio Code, a new development tool for Windows, Linux and Mac OS, mostly focused on web development (ASP.NET and Node.JS) even if [Read more...]


Wine 1.7.42 Released, Install/Update In Ubuntu/Linux Mint

Wine 1.7.42 Released, Install/Update In Ubuntu/Linux Mint

Wine is an Open Source, command line and most popular software that allows users to install and run Microsoft Windows applications and games on Linux. Wine Team recently released Wine 1.7.42 development version with many bug fixes and improvements. Let's see what's new in this release.

Read At LinuxAndUbuntu


Set up Nova-Docker Driver on OpenStack RDO Kilo (RC2) on CentOS 7.1

Posting bellow is targeting testing official version of Nova-Doker Driver for Openstack Kilo with development version RDO Kilo ( supposed GA day is 05/07/2015).  RDO Kilo installed via `packstack --allinone` on virtual CentOS 7.1 machine running at  Fedora 21 KVM Hypervisor. The only one package python-pip was rebuilt via Fedora Rawhide Repos and re installed on CentOS 7.1 to satisfy requirements for  successful build of Nova-Docker driver. Native  version of docker-io is 1.5 and supports  driver build as is. Regarding details of pulling in docker images and uploading to glance, please, view Setup Nova-Docker driver && Openstack Kilo on Ubuntu 14.04 in devstack environment recoverable between reboots

Cimplete text may be viewed here


Setup NovaDocker driver && Openstack Kilo on Ubuntu 14.04 ( devstack ) recoverable between reboots

Step by step instruction for  setting up  Nova-Docker driver && Openstack Kilo on Ubuntu 14.04 in devstack environment recoverable between reboots. Also routing across LAN is described for remote access to Devstack ( public network. I've tried to cover all known as of time of writing problems preventing ./ from successful run. However , I cannot issue any warranty that tomorrow new daemon won't rejoin stack instance after reboot. The only way for safe solution would be RDO Kilo Release expected in may of 2015 (for myself of course). This post is written with major concern of successful loading by Kilo Nova-Docker Driver in development environment.

Complete text of article may be viewed here


What are good command line HTTP clients?

The whole is greater than the sum of its parts is a very famous quote from Aristotle, a Greek philosopher and scientist. This quote is particularly pertinent to Linux. In my view, one of Linux's biggest strengths is its synergy. The usefulness of Linux doesn't derive only from the huge raft of open source (command line) utilities. Instead, it's the synergy generated by using them together, sometimes in conjunction with larger applications.

This article looks at 3 open source command line HTTP clients. These clients let you download files off the internet from a command line. But they can also be used for many more interesting purposes such as testing, debugging and interacting with HTTP servers and web applications. Working with HTTP from the command-line is a worthwhile skill for HTTP architects and API designers. If you need to play around with an API, HTTPie and cURL will be invaluable.

[url=]Read more[/url]


KDE Plasma 5 on Arch Linux review

Plasma 5 on Arch Linux

A few weeks ago, during a little break from studies, I’ve finally found some time for installingPlasma 5 on my Arch Linux workstation. Before a not too deep period of usage I’d like to share with you my impressions on the current state of Plasma.

As the title says, I’m going to talk about the 5.2 version of Plasma so everything on this post will concern this version in particular.

If you’re a Linux user at least from 2007 and, above all, you were using Kde at time, you will surely remember (Read more...)


30 Things to Do After Minimal RHEL/CentOS 7 Installation

                                         30 Things to Do After Minimal RHEL/CentOS 7 Installation


CentOS is a Industry Standard Linux Distribution which is a derivative of RedHat Enterprise Linux. You may start using the OS as soon as you install it, but to make the most out of your system you need to perform a few updates, install a few packages, configure certain services and application.

This article aims at “30 Things to Do After Installing RHEL/CentOS 7”. The post is written keeping in mind you have installed RHEL/CentOS Minimal Install which is preferred in Enterprise and production environment, if not you can follow below guide that will show you minimal installations of both.

  1. Installation of CentOS 7 Minimal
  2. Installation of RHEL 7 Minimal

The following are the list of important things, which we’ve covered in this guide based on industry standard requirements. We hoping that, these things will be very helpful in setting up your server.

1. Register and Enable Red Hat Subscription

After minimal RHEL 7 installation, it’s time to register and enable your system to Red Hat Subscription repositories and perform a full system update. This is valid only if you have a valid RedHat Subscription. You need to register your in order to enable official RedHat System repositories and update the OS from time-to-time.

We have already covered a detailed instructions on how to register and active RedHat subscription at the below guide.

  1. Register and Enable Red Hat Subscription Repositories in RHEL 7

Note: This step is only for RedHat Enterprise Linux having a valid subscription. If you are running a CentOS server immediately move to further steps.

2. Configure Network with Static IP Address

The first thing you need to do is to configure Static IP address, Route and DNS to your CentOS Server. We will be using ip command the replacement of ifconfig command. However, ifconfig command is still available for most of the Linux distributions and can be installed from default repository.

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